Semiconductor device, communication system, and method of charging the semiconductor device

ABSTRACT

An object of the present invention to provide a semiconductor device including a battery that can be wirelessly charged, in which the battery can be charged even when the semiconductor device is not put close to a power feeder. Such a semiconductor device has a structure including an antenna circuit, a communication control circuit to conduct wireless communication via the antenna circuit, a battery to be charged with electric power which is externally wirelessly fed via the antenna circuit, and an oscillator circuit to wirelessly feed electric power via the antenna circuit. In addition, the battery in the semiconductor device is wirelessly charged and the semiconductor device externally feeds electric power wirelessly to a chargeable battery in another semiconductor device.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a semiconductor device including abattery that can be wirelessly charged.

2. Description of the Related Art

In recent years, various electric appliances come into wide use, and awide variety of products are put on the market. In particular, thespread of portable wireless communication devices is notable. A powersupply for driving a portable wireless communication device has abuilt-in battery which is chargeable and power is supplied from thebattery into the portable wireless communication device. As the battery,a secondary cell such as a lithium ion battery or the like is generallyused. As matters now stand, the battery is charged from an AC adaptorwhich is plugged into a household alternating current power supply.

Further, in recent years, an individual identification technology whichemploys wireless communication which uses an electromagnetic field,radio waves, or the like has attracted attention as one mode of usage ofwireless communication devices. In particular, an individualidentification technology which employs an RFID (radio frequencyidentification) tag that communicates data wirelessly has attractedattention. An RFID tag is also referred to as an IC (integrated circuit)tag, an IC chip, an RF tag, a wireless tag, and an electronic tag. Theindividual identification technology which employs RFID tags isbeginning to be made use of in production, management, and the like ofindividual objects, and it is expected that this technology will also beapplied to personal authentication, through inclusion in cards or thelike.

In addition, development is advanced recently for a contactless chargingdevice in which a battery is charged with using a combination of aprimary coil provided to a power feeder for charging the battery, and asecondary coil provided to a device including the battery (e.g., PatentDocument 1: Japanese Published Patent Application No. H10-14126).

SUMMARY OF THE INVENTION

However, in the case of charging the battery by arranging the primarycoil of the power feeder and the secondary coil of the device includingthe battery close to each other, the power feeder and the deviceincluding the battery need to be put close to each other. Accordingly,in the case where there are a plurality of semiconductor devicesprovided with batteries, the power feeder needs to be put close to eachof the plurality of semiconductor devices in order to charge theirbatteries. Further, when a semiconductor device including a battery thatcan be wirelessly charged is used for product management or the like,places of the power feeder and the semiconductor device need dueconsideration.

In accordance with the foregoing problems, it is an object of thepresent invention to provide a semiconductor device including a batterythat can be wirelessly charged in a simple manner. In addition, it isanother object of the present invention to provide a semiconductordevice including a battery that can be wirelessly charged, even when apower feeder is not put close to the semiconductor device including thebattery which can be wirelessly charged.

A semiconductor device of the present invention includes a battery thatcan be wirelessly charged, in which the battery can be charged using anelectromagnetic wave transmitted from another semiconductor device. Inaddition, the semiconductor device of the present invention has astructure which transmits an electromagnetic wave to anothersemiconductor device so as to charge a battery therein. In other words,the semiconductor device of the present invention has a function offeeding or receiving electric power to or from another semiconductordevice, as well as a function of charging using an electromagnetic wavetransmitted from a power feeder. In addition, the semiconductor deviceof the present invention can have a structure in which the semiconductordevice communicates with another semiconductor device to transmit andreceive information. Details of a structure of the present invention arehereinafter described.

A semiconductor device of the present invention includes an antennacircuit, a communication control circuit to conduct wirelesscommunication externally via the antenna circuit, a battery to becharged with electric power which is externally wirelessly fed via theantenna circuit, and an oscillator circuit to wirelessly feed electricpower via the antenna circuit. In other words, a semiconductor device ofthe present invention has a structure in which the battery in thesemiconductor device is wirelessly charged and the semiconductor deviceexternally feeds electric power to a battery in another semiconductordevice which can be charged wirelessly.

Another semiconductor device of the present invention includes anantenna circuit; a communication control circuit to conduct wirelesscommunication externally via the antenna circuit; a battery to becharged with electric power externally fed via the antenna circuit; acomparison arithmetic circuit to compare a state of charge of thebattery and a state of charge of another battery in anothersemiconductor device, which is obtained by external communication; andan oscillator circuit which is capable of wirelessly feeding electricpower to the another battery. A state of charge of the battery in thesemiconductor device and that of the another battery in the anothersemiconductor device are compared and power can be fed from thesemiconductor device with larger amount of charge to the semiconductordevice with smaller amount of charge.

Another semiconductor device of the present invention includes anantenna circuit; a communication control circuit to conduct wirelesscommunication externally via the antenna circuit; a battery to becharged with electric power externally fed via the antenna circuit; adata converter circuit to convert a state of charge of the battery intoa digital value; a comparison arithmetic circuit to compare the state ofcharge of the battery, which is converted into the digital value by thedata converter circuit, and a state of charge of another battery inanother semiconductor device, which is obtained by externalcommunication; and an oscillator circuit which is capable of wirelesslyfeeding electric power to the another battery.

Another semiconductor device of the present invention includes a firstantenna circuit; a second antenna circuit; a communication controlcircuit to conduct wireless communication externally via the firstantenna circuit; a battery to be charged with electric power externallyfed via the second antenna circuit; a comparison arithmetic circuit tocompare a state of charge of the battery and a state of charge ofanother battery in another semiconductor circuit, which is obtained byexternal communication; and an oscillator circuit which is capable ofwirelessly feeding electric power to the another battery via the secondantenna circuit.

Another semiconductor device of the present invention includes a firstantenna circuit; a second antenna circuit; a communication controlcircuit to conduct wireless communication externally via the firstantenna circuit; a battery to be charged with electric power externallyfed via the second antenna circuit; a data converter circuit to converta state of charge of the battery into a digital value; a comparisonarithmetic circuit to compare the state of charge of the battery, whichis converted into the digital value by the data converter circuit, and astate of charge of another battery in another semiconductor circuit,which is obtained by external communication; and an oscillator circuitwhich is capable of wirelessly feeding electric power to the anotherbattery via the second antenna circuit.

In a semiconductor device of the present invention having any of theforegoing structures, the shape of a first antenna provided in the firstantenna circuit and the shape of a second antenna provided in the secondantenna circuit can be different from each other. For example, one ofthe first antenna and the second antenna may have a coil-shape.

In semiconductor devices each including a battery that can be wirelesslycharged, a structure in which electric power of the batteries is fed andreceived between the semiconductor devices is realized, and therefore, apower feeder is not necessarily put close to each of the plurality ofsemiconductor devices for charging. As a result, a semiconductor deviceincluding a battery that can be wirelessly charged in a simple mannercan be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates communication or feeding and receiving of electricpower between semiconductor devices of the present invention;

FIG. 2 illustrates an example of a semiconductor device of the presentinvention;

FIG. 3 illustrates an example of a semiconductor device of the presentinvention;

FIGS. 4A and 4B illustrate an example of antenna circuit and an exampleof a rectifier circuit, respectively;

FIGS. 5A and 5B each illustrate an example of a charge control circuitof a semiconductor device of the present invention;

FIGS. 6A and 6B each illustrate an example of a data converter circuitof a semiconductor device of the present invention;

FIGS. 7A and 7B each illustrate an example of a semiconductor device ofthe present invention;

FIG. 8 illustrates an example of feeding and receiving electric powerbetween semiconductor devices of the present invention;

FIG. 9 illustrates an example of feeding and receiving electric powerbetween semiconductor devices of the present invention;

FIG. 10 illustrates an example of a semiconductor device of the presentinvention;

FIGS. 11A to 11C illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 12A to 12C illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 13A and 13B illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 14A to 14C illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 15A to 15C illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 16A to 16C illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 17A and 17B illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 18A to 18D illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 19A to 19C illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 20A and 20B illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 21A and 21B illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 22A and 22B illustrate an example of a method of manufacturing asemiconductor device of the present invention;

FIGS. 23A to 23E each illustrate an example of mode of usage of asemiconductor device of the present invention; and

FIGS. 24A to 24D each illustrate an example of mode of usage of asemiconductor device of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, embodiment modes of the present invention are describedwith reference to the drawings. The present invention can be carried outin many different modes, and it is easily understood by those skilled inthe art that modes and details can be modified in various ways withoutdeparting from the purpose and the scope of the present invention.Accordingly, the present invention should not be interpreted as beinglimited to the description of the embodiment modes to be given below.Note that like portions in the drawings for describing embodiment modesare denoted by the like reference numerals and repeated explanationsthereof are omitted.

Embodiment Mode 1

A semiconductor device of the present invention includes a battery thatcan be wirelessly charged, and has a structure in which thesemiconductor device feeds or receives electric power of the battery toor from another semiconductor device. In other words, as shown in FIG.1, a semiconductor device of the present invention not only receives anelectromagnetic wave from a reader/writer 190 serving as a power feederto charge a battery included in the semiconductor device, but also cancommunicate with another semiconductor device 101 a or 101 b having asimilar structure in order to feed or receive electric power. Inaddition, the semiconductor device 101 b can also communicate withanother semiconductor device 101 c which is within a predetermined areain order to feed or receive electric power.

Specific structures of a semiconductor device of the present inventionare described hereinafter with reference to drawings.

The semiconductor device 101 described in this embodiment mode includesan antenna circuit 111, a communication control circuit 125, a battery118, a data converter circuit 120, a comparison arithmetic circuit 121,and an oscillator circuit 122 (see FIG. 2). The semiconductor device 101wirelessly communicates with and feeds or receives electric power to orfrom an external reader/writer or another semiconductor device.

The antenna circuit 111 may have a function of transmitting andreceiving a communication signal (an electromagnetic wave); for example,an antenna 141 and a resonant capacitor 142 can form the antenna circuit111 as shown in FIG. 4A. Here, the antenna 141 and the resonantcapacitor 142 are collectively referred to as the antenna circuit 111.The shape of the antenna 141 may be decided in accordance with anelectromagnetic wave used for communication. For example, in the case ofusing an electromagnetic induction method, a coil can be used; in thecase of using an electric field method, a structure provided with adipole antenna can be employed.

The communication control circuit 125 has a function of controllingwireless external communication via the antenna circuit 111 andtransmits and receives information to and from the reader/writer oranother semiconductor device. For example, the communication controlcircuit 125 transmits information on the semiconductor device 101 inresponse to a signal from the reader/writer, then, an electromagneticwave is transmitted from the reader/writer based on the information inorder to charge the battery 118. In addition, the communication controlcircuit 125 transmits and receives information on a state of charge of abattery provided in another semiconductor device to and from the anothersemiconductor device; based on the result thereof, electric power is fedor received and information is transmitted and received between thesemiconductor devices.

In addition, the communication control circuit 125 includes ademodulation circuit 112, a logic circuit 113, a memory circuit 114, amodulation circuit 115, and the like. The demodulation circuit 112 has afunction of extracting reception data from the communication signal; forexample, the demodulation circuit 112 may be a low pass filter (LPF).The logic circuit 113, for example, determines whether to carry outwriting to the memory circuit 114 or not depending on the data stored inthe memory circuit 114, and controls another circuit. The memory circuit114 stores information for individual identification and another pieceof information. A nonvolatile memory may be the memory circuit 114, forexample. The modulation circuit 115 has a function of superimposingtransmission data on the communication signal.

In addition, the communication control circuit 125 can be driven withelectric power which is fed from the battery 118. Further, a structuremay be employed in which a power supply circuit which generates powersource voltage from the communication signal is provided in thecommunication control circuit 125 and the communication control circuit125 is driven by electric power from the power supply circuit.

The battery 118 has a function of being charged with electric powerwhich is externally fed. Here, the communication signal is received bythe antenna circuit 111, and then, the electric power can be fed to thebattery 118 via a rectifier circuit 116 and a charge control circuit117.

The rectifier circuit 116 may be any circuit which converts an ACsignal, which has been induced by an electromagnetic wave received bythe antenna circuit 111, into a DC signal. The rectifier circuit 116mainly includes a diode and a smoothing capacitor. The rectifier circuit116 may also include a resistor or a capacitor in order to adjustimpedance. For example, as shown in FIG. 4B, the rectifier circuit 116may include a diode 143, and a smoothing capacitor 144.

The charge control circuit 117 may be any circuit which controls avoltage level of an electric signal inputted from the rectifier circuit116 and outputs the electric signal to the battery 118. For example, thecharge control circuit 117 can include a regulator 145 which is acircuit which controls voltage, and a diode 146 which has rectifyingcharacteristics, as shown in FIG. 5A. The diode 146 prevents leakage ofelectric power which the battery 118 charges. Therefore, a structure inwhich the diode 146 is replaced with a switch 147 may be employed, asshown in FIG. 5B. In the case of providing the switch 147, leakage ofelectric power in the battery 118 can be prevented by turning the switchon when the battery 118 is being charged and off when the battery 118 isnot being charged.

In the present invention, ‘battery’ refers to power storage means ofwhich electric power can be restored by being charged. Note that aspower storage means, there are a secondary cell, a capacitor, and thelike; however, in this specification, these power storage means arereferred to under the general term ‘battery’. As a battery, although thetype of battery may differ depending on an intended use, a batteryformed with a sheet-like shape is preferably used. For example, when alithium battery, preferably a lithium polymer battery that uses a gelelectrolyte, a lithium ion battery, or the like, miniaturization ispossible. Needless to say, any battery may be used as long as it ischargeable. A battery that can be charged and discharged, such as anickel metal hydride battery, a nickel cadmium battery, an organicradical battery, a lead-acid battery, an air secondary battery, anickel-zinc battery, or a silver-zinc battery may be used. Ahigh-capacity capacitor or the like may also be used.

Note that as a high-capacity capacitor which can be used as a battery inthe present invention, a capacitor having electrodes whose opposingareas are large is preferable. It is preferable to use a double-layerelectrolytic capacitor which employs an electrode material having alarge specific surface area such as activated carbon, fullerene, or acarbon nanotube. Further, a capacitor can be easily formed to be thinand formed by stacking layers. A double-layer electrolytic capacitor ispreferable because it has a function of storing power and will notdeteriorate much even after being charged and discharged a number oftimes. In addition, the double-layer electrolytic capacitor can becharged quickly.

Note that in this embodiment mode, electric power that is stored in thebattery is not limited to an electromagnetic wave received by theantenna circuit 111. A structure may be employed in which a powergeneration element is supplementarily provided in a part of thesemiconductor device. Employing a structure in which a power generationelement is provided in the semiconductor device is preferable becausewhen such a structure is employed, the amount of electric power fed tobe stored in the battery 118 can be increased and the charging rate canbe increased. A power generation element may be, for example, a powergeneration element which employs a solar cell, a power generationelement which employs a piezoelectric element, or a power generationelement which employs a micro electro mechanical system (MEMS).

The data converter circuit 120 has a function of converting a state ofcharge (the amount of charge remaining) in the battery 118 from ananalog value into a digital value. For example, the capacity of battery118 may be rated on a scale of n-th stages and the data convertercircuit 120 detects which stage the amount of charge remaining in thebattery is in. One example of the data converter circuit 120 is shown inFIG. 6A. Here, the case is described in which the amount of chargeremaining in the battery 118 is detected using the scale of level1-to-n.

The data converter circuit 120 includes an input terminal 161, first ton-th comparators 160 _(—1) to 160 _(—n), and first to n-th outputterminals 162 _(—1) to 162 _(—n). The input terminal 161 is electricallyconnected to the battery 118 and voltage of the battery 118 is inputtedthereto.

Each of the first to n-th comparators 160 _(—1) to 160 _(—n) may be anycircuit which compares values of two inputted signals and outputs theresult of the comparison. Here, each of the comparators has two inputportions and one output portion. In the first comparator 160 _(—1), asignal (the voltage of the battery 118) is inputted to one of the inputportions from the input terminal 161 and a first reference voltage isinputted to the other input portion. The first comparator 160 _(—1) thencompares the values of the two inputted voltages and outputs the resultto the first output terminal 162 _(—1). Similarly, in each of the secondto n-th comparators 160 _(—2) to 160 _(—n), a signal is inputted to oneof the input portions from the input terminal 161 and the correspondingone of second to n-th reference voltages is inputted to the other inputportion, and the comparison result of the two inputted signals isoutputted to one of the output terminals 162 _(—2) to 162 _(—n).

In the data converter circuit 120, the first to n-th reference voltagesrange from smallest to largest in that order (the first referencevoltage>the second reference voltage>the third reference voltage> . .. >the n-th reference voltage); therefore, the level to which the amountof charge remaining in the battery 118 corresponds to can be detected.

For example, in the case of using a battery which can charge up to 5V asthe battery 118, the first to fourth comparators 160 _(—1) to 160 _(—4)are provided (the case where n=4 in FIG. 6A), and the first referencevoltage is 1 V, the second reference voltage is 2 V, the third referencevoltage is 3 V, and the fourth reference voltage is 4 V. Then, thevoltage inputted from the battery 118 and is compared with each of thereference voltages and the level of the amount of charge remaining inthe battery 118 is determined according to the comparison result. Forexample, a voltage of larger than or equal to 0 V (which is a state inwhich the battery is not charged at all) and smaller than 1 V can beLevel 1, a voltage of larger than or equal to 1 V and smaller than 2 Vcan be Level 2, a voltage of larger than or equal to 2 V and smallerthan 3 V can be Level 3, a voltage of larger than or equal to 3 V andsmaller than 4 V can be Level 4, and a voltage of larger than or equalto 4 V and smaller than or equal to 5 V (which is a state in which thebattery is fully charged) can be Level 5.

In this manner, by using data converter circuit 120, the amount ofcharge remaining in the battery 118 can be converted into a digitalvalue.

Note that the structure of the data converter circuit 120 is not limitedto the one shown in FIG. 6A. For example, the one shown in FIG. 6B maybe employed.

The data converter circuit 120 shown in FIG. 6B includes the inputterminal 161, the comparator 160, and the output terminal 162. The inputterminal 161 is electrically connected to the battery 118 and thevoltage of the battery 118 is inputted thereto.

In this case, a signal is inputted to one of the input portions in thecomparator from the input terminal 161 and the first to n-th referencevoltages are sequentially inputted to the other input portion. Thecomparator compares signals inputted to the one input terminal and theother input terminal and outputs the result to the output terminal 162.For example, when the voltage of the battery 118 is larger or equal toan m-th reference voltage and smaller than or equal to an (m+1)-threference voltage, (Vi+1), the results corresponding to the inputs ofthe first to m-th reference voltages (for example, the output is “1”)are different from the results corresponding to the inputs of the(m+1)-th to n-th reference voltages (for example, the output is “0”).Therefore, the level of the state of charge in the battery 118 can bedetected.

Note that in the case of comparing the amount of charge remaining in thebatteries in analog values, a structure in which the data convertercircuit 120 is not provided in the semiconductor device 101 may beprovided.

The comparison arithmetic circuit 121 has a function of comparing thestate of the battery 118, which is converted by the data convertercircuit 120, and a state of a battery in another semiconductor device,which is received via the communication control circuit 125. As a resultof the comparison in the comparison arithmetic circuit 121, when theamount of charge remaining in the battery 118 provided in thesemiconductor device 101 is larger than that in the battery in the othersemiconductor device, electric power is fed from the oscillator circuit122 to the other semiconductor device via the antenna circuit 111.

The oscillator circuit 122 has a function of feeding electric power bytransmitting an electromagnetic wave to the other semiconductor device,when there is an instruction from the comparison arithmetic circuit 121.The oscillator circuit 122 may be any circuit which can transmit anelectromagnetic wave via the antenna circuit 111.

Thus, by employing a structure in which electric power of the batteriesis fed and received between the semiconductor devices, the necessity toplace a power feeder close to each of the plurality of semiconductordevices to conduct charging is eliminated. In addition, because astructure in which communication is performed between the semiconductordevices is employed, it is not necessary to place a reader/writer closeto each of the plurality of semiconductor devices to read information,and as a result, the communication distance can be increased.

Note that a structure of a semiconductor device in this embodiment modecan be implemented by being combined with a structure of a semiconductordevice in another embodiment mode described in this specification.

Embodiment Mode 2

In this embodiment mode, a semiconductor device which is different fromthat described in the foregoing embodiment mode is described withreference to the drawings.

A semiconductor device in this embodiment mode has a structure in whicha plurality of antenna circuits are provided. The case of providing twoantenna circuits, a first antenna circuit 151 and a second antennacircuit 152, is described hereinafter.

The semiconductor device 101 described in this embodiment mode includesthe first antenna circuit 151, the second antenna circuit 152, thecommunication control circuit 125, the battery 118, the data convertercircuit 120, the comparison arithmetic circuit 121, and the oscillatorcircuit 122 (see FIG. 3). Each of the first antenna circuit 151 and thesecond antenna circuit 152 may have a structure having a function oftransmitting and receiving a communication signal (an electromagneticwave); for example, the antenna 141 and the resonant capacitor 142 canform the antenna circuit, as shown in FIG. 4A.

The communication control circuit 125 wirelessly communicates with areader/writer and another semiconductor device via the first antennacircuit 151. In addition, a structure can be employed in which chargingof electric power to the battery 118 and transmission of anelectromagnetic wave to the other semiconductor device from theoscillator circuit 122 are performed via the second antenna circuit 152.

The shapes of the first antenna circuit 151 and the second antennacircuit 152 may be decided taking an electromagnetic wave which is usedfor communication into consideration. For example, in the case of usingan electromagnetic induction method, a coil can be used, and in the caseof using an electric field method, a structure provided with a dipoleantenna can be employed. Further, the first antenna circuit 151 and thesecond antenna circuit 152 may have shapes such that they receive thesame wave length or receive different wave lengths. For example, one ofthe first antenna circuit 151 and the second antenna circuit 152 may bea dipole antenna and the other one may be a coil.

For example, as shown in FIG. 7A, a 180 degrees omnidirectional (canreceive signals equally from any direction) antenna 2902 a which isprovided as an antenna in the first antenna circuit 151 and a sheetantenna 2902 b which is provided as an antenna in second antenna circuit152 can be provided around a chip 2901 provided with the communicationcontrol circuit 125, the battery 118, the oscillator circuit 122, andthe like. Needless to say, alternatively the antenna 2902 b may beprovided as the antenna in the first antenna circuit 151 and the antenna2902 a may be provided as the antenna in the second antenna circuit 152.

Alternatively, a structure may be employed in which the second antennacircuit 152, which is used to charge electric power to the battery 118,includes two antennas. For example, as shown in FIG. 7B, an antenna 2902c for receiving a high frequency electromagnetic wave, which is anantenna in the first antenna circuit 151, and an antenna 2902 d whichextends in a long rod-shape and an antenna 2902 e with a thin coiledshape, which are antennas in the second antenna circuit 152, can beprovided around the chip 2901 provided with the communication controlcircuit 125, the battery 118, the oscillator circuit 122, and the like.Needless to say, the antennas 2902 d and 2902 e may be provided as theantennas in the first antenna circuit 151 and the antenna 2902 c may beprovided as the antenna in the second antenna circuit 152. When antennashaving a plurality of shapes are thus provided, a semiconductor whichcan receive electromagnetic with different frequency bands (for example,an electromagnetic wave from a power feeder and electromagnetic wavesgenerated at random outside) can be formed.

Note that although a structure in which two antenna circuits areprovided is shown in FIG. 3, the structure is not limited thereto, and astructure in which three or more antenna circuits are provided may beemployed. For example, as shown in FIG. 10, a structure in which threeantenna circuits, the first to third antenna circuits 151 to 153, areprovided may be employed.

In FIG. 10, the communication control circuit 125 wirelesslycommunicates with the reader/writer and another semiconductor device viathe first antenna circuit 151. In addition, a structure can be employedin which charging of electric power to the battery 118 and transmissionof an electromagnetic wave to the other semiconductor device from theoscillator circuit 122 are performed via the second antenna circuit 152or the third antenna circuit 153. A structure can be employed in whichthe battery 118 is charged using an electromagnetic wave received by thesecond antenna circuit 152 which is supplied to the battery 118 via therectifier circuit 116 and the charge control circuit 117. Alternatively,a structure can be employed in which the battery 118 is charged using anelectromagnetic wave received by the third antenna circuit 153 which issupplied to the battery 118 via a rectifier circuit 154 and the chargecontrol circuit 155. Further, when a structure is employed in which thesecond antenna circuit 152 and the third antenna circuit 153 receivedifferent wave lengths, a plurality of wave lengths can be used forcharging the battery 118. For example, one of an antenna of the secondantenna circuit 152 and an antenna of the third antenna circuit 153 canbe a coil to which an electromagnetic induction method is applied andthe other one can be a dipole antenna to which an electric field methodis applied.

When a plurality of antenna circuits are thus provided, communication ofthe communication control circuit 125 and the charging of the battery118 can be carried out using different frequencies.

Note that a structure of a semiconductor device in this embodiment modecan be implemented by being combined with a structure of a semiconductordevice in another embodiment mode described in this specification.

Embodiment Mode 3

In this embodiment mode, the case in which a semiconductor device feedsor receives electric power to or from a reader/writer or anothersemiconductor device is described with reference to the drawings.

First, the case is described in which a semiconductor device whichreceives electric power from a reader/writer feeds or receives electricpower to or from another semiconductor device, with reference to FIG. 8.

When the semiconductor device comes into a communication range of thereader/writer, the semiconductor device starts to receive anelectromagnetic wave which is transmitted from the reader/writer (201).Then, the reader/writer detects a state of charge of a battery in thesemiconductor device. Here, the reader/writer detects whether thebattery in the semiconductor device has a voltage equal to or largerthan a predetermined voltage value (e.g., Vx) (202). If the voltage ofthe battery, V1, is smaller than Vx, the battery starts to be charged byreceiving an electromagnetic wave transmitted from the reader/writer(203). When the voltage of the battery, V1, becomes equal to or largerthan the predetermined voltage value (Vx), the battery stops beingcharged (204). Note that charging can be stopped by turning off a switchprovided in the semiconductor device when the voltage of the batteryequals or exceeds the predetermined voltage value. Alternatively, astructure can be employed in which when the voltage of the batteryequals or exceeds the predetermined voltage value, a signal istransmitted from the semiconductor device to the reader/writer to stopthe transmission of electromagnetic waves from the reader/writer.

Next, when the semiconductor device (hereinafter referred to as a firstsemiconductor device) moves (205) and finds another semiconductor device(hereinafter referred to as a second semiconductor device) (206), thefirst semiconductor device communicates with the found secondsemiconductor device and detects a state of charge of a battery in thesecond semiconductor device (and the second semiconductor device detectsa state of charge of the battery in the first semiconductor device)(207). Note that although the case in which the first semiconductordevice moves and finds the second semiconductor device is described asan example here, there is also a case in which the first semiconductordevice finds the second semiconductor device without moving, and detectsthe state of charge of the second semiconductor device.

Next, in a comparison arithmetic circuit provided in the firstsemiconductor device, the voltage of the battery in the firstsemiconductor device, V1, and voltage of the battery in the found secondsemiconductor device, V2, are compared (208). If the comparison revealsthat the voltage of the battery in the first semiconductor device, V1,is larger than the voltage of the battery in the second semiconductordevice, V2, (i.e., V1>V2), an electromagnetic wave is transmitted froman oscillator circuit in the first semiconductor device, so thatelectric power is fed to the battery in the second semiconductor device(209). If the voltage of the battery in the first semiconductor device,V1, is smaller than the voltage of the battery in the secondsemiconductor device, V2, (i.e., V1<V2), the first semiconductor devicereceives electromagnetic wave which is transmitted from an oscillatorcircuit in the second semiconductor device, so that the battery in thefirst semiconductor device receives electric power (210). When thevoltage of the battery in the first semiconductor device and that of thebattery in the second semiconductor device become equal (i.e., V1=V2),feeding and receiving of electric power between the first semiconductordevice and the second semiconductor device stop (211). Note that here,becoming equal includes becoming approximately equal.

Note that although FIG. 8 shows an example in which the firstsemiconductor device feeds or receives electric power to or from thesecond semiconductor device until the voltage of the battery in thefirst semiconductor device, V1, and the voltage of the battery in thesecond semiconductor device, V2, become approximately equal, the presentinvention is not limited thereto. For example, a structure may beemployed in which even when the voltage of the battery in the firstsemiconductor device, V1, and the voltage of the battery in the secondsemiconductor device, V2, are different from each other; when V1 and V2are each larger than or equal to a predetermined voltage (e.g., Vy), thefirst semiconductor device and the second semiconductor device do notfeed or receive electric power to or from each other. This case isbriefly described with reference to FIG. 9.

In FIG. 9, the following steps can be carried out similarly to those inFIG. 8: the step (206) in which the first semiconductor device finds thesecond semiconductor device, the following step, (207), in which thefirst semiconductor device communicates with the second semiconductordevice, and the step (208) in which the voltage of the battery in thefirst semiconductor device, V1, and the voltage of the battery in thefound second semiconductor device, V2, are compared.

If the comparison of V1 and V2 reveals that V1 and V2 are each largerthan or equal to the predetermined voltage Vy (i.e., V1≧Vy and V2≧Vy),or V1 and V2 are each smaller than the predetermined voltage Vy (i.e.,V1<Vy and V2<Vy), the first semiconductor device and the secondsemiconductor device finish their communication without feeding andreceiving electric power to or from each other (211). Thus, in the casewhere both of the batteries in the first and second semiconductordevices have enough electric power, or in the case where both of thebatteries in the first and second semiconductor devices do not haveenough electric power, the first semiconductor device and the secondsemiconductor device do not feed or receive electric power to or fromeach other; therefore, electric power in the batteries can be preventedfrom being wasted.

Further, if V1 is larger than the predetermined voltage Vy and V2 issmaller than the predetermined voltage Vy, (i.e., V1>Vy and V2<Vy), anelectromagnetic wave is transmitted from the oscillator circuit in thefirst semiconductor device, so that electric power is fed to the batteryin the second semiconductor device (209). The voltage of the battery inthe first semiconductor device, V1 and the voltage of the battery in thesecond semiconductor device, V2 are compared (221). When the voltage ofthe battery in the first semiconductor device V1 is decreased andbecomes equal to the level of the predetermined voltage Vy (i.e.,V1=Vy), or the voltage of the battery in the first semiconductor deviceand that of the battery in the second semiconductor device become equal(i.e., V1=V2), feeding and receiving of electric power between the firstsemiconductor device and the second semiconductor device stop (211).Note that here, becoming equal includes becoming approximately equal.Thus, transmission of the electromagnetic wave is stopped when thevoltage of the battery in the first semiconductor device becomes equalto the predetermined voltage, and therefore, a predetermined amount ofelectric power can be maintained in the first semiconductor device.

Further, if V1 is smaller than the predetermined voltage Vy and V2 islarger than the predetermined voltage Vy (i.e., V1<Vy and V2>Vy), thefirst semiconductor device receives an electromagnetic wave which istransmitted from the oscillator circuit in the second semiconductordevice, so the battery in the first semiconductor device receiveselectric power (210). The voltage of the battery in the firstsemiconductor device, V1 and the voltage of the battery in the secondsemiconductor device, V2 are compared (222). When the voltage of thebattery in the second semiconductor device V2 is decreased and becomesequal to the level of the predetermined voltage Vy (i.e., V2=Vy), or thevoltage of the battery in the first semiconductor device and that of thebattery in the second semiconductor device become equal (i.e., V1=V2),feeding and receiving of electric power between the first semiconductordevice and the second semiconductor device stop (211). Note that here,becoming equal includes becoming approximately equal. Thus, transmissionof the electromagnetic wave is stopped when the voltage of the batteryin the second semiconductor device becomes equal to the predeterminedvoltage, and therefore, a predetermined amount of electric power can bemaintained in the second semiconductor device.

Note that in the foregoing description, when the first semiconductordevice finds a plurality of the semiconductor devices, the firstsemiconductor device may preferentially feed or receive electric powerto or from a semiconductor device whose battery has the lowest voltageof the batteries of those semiconductor devices.

Note that a structure of a semiconductor device in this embodiment modecan be implemented by being combined with a structure of a semiconductordevice in another embodiment mode described in this specification.

Embodiment Mode 4

In this embodiment mode, an example of a method of manufacturing asemiconductor device described in any of the foregoing embodiment modesis described with reference to the drawings. In this embodiment mode, astructure in which a communication control circuit, a rectifier circuit,a charge control circuit, and the like of a semiconductor device areformed over one substrate using thin film transistors is described. Notethat it is preferable to form a communication control circuit, arectifier circuit, a charge control circuit, and the like over onesubstrate at one time, because this can lead to reduction in size. Inaddition, an example in which a thin-film secondary battery is used as abattery is described. Needless to say, a double-layer electrolyticcapacitor or the like may be provided instead of a secondary battery.

First, a peeling layer 1303 is formed over one surface of a substrate1301 with an insulating film 1302 therebetween, and then an insulatingfilm 1304 serving as a base film and a semiconductor film (e.g., anamorphous semiconductor film 1305) are stacked thereover (see FIG. 18A).Note that the insulating film 1302, the peeling layer 1303, theinsulating film 1304, and the amorphous semiconductor film 1305 can beformed consecutively.

The substrate 1301 is selected from a glass substrate, a quartzsubstrate, a metal substrate (e.g., a stainless steel substrate), aceramic substrate, a semiconductor substrate such as a Si substrate, asilicon insulator (SOI) substrate, and the like. Alternatively, aplastic substrate made of polyethylene terephthalate (PET), polyethylenenaphthalate (PEN), polyether sulfone (PES), acrylic, or the like can beused. In this process, although the peeling layer 1303 is provided overthe entire surface of the substrate 1301 with the insulating film 1302therebetween, the peeling layer 1303 can be selectively formed by aphotolithography method after being provided over the entire surface ofthe substrate 1301.

The insulating films 1302 and 1304 are formed using insulating materialssuch as silicon oxide, silicon nitride, silicon oxynitride(SiO_(x)N_(y), where x>y), or silicon nitride oxide (SiN_(x)O_(y), wherex>y) by a CVD method, a sputtering method, or the like. For example,when each of the insulating films 1302 and 1304 is formed to have atwo-layer structure, a silicon nitride oxide film may be formed as afirst insulating film and a silicon oxynitride film may be formed as asecond insulating film. In addition, a silicon nitride film may beformed as the first insulating film and a silicon oxide film may beformed as the second insulating film. The insulating film 1302 serves asa blocking layer which prevents an impurity element contained in thesubstrate 1301 from getting mixed into the peeling layer 1303 orelements formed thereover. The insulating film 1304 serves as a blockinglayer which prevents an impurity element contained in the substrate 1301or the peeling layer 1303 from getting mixed into elements formed overthe insulating film 1304. In this manner, providing the insulating films1302 and 1304 which serve as the blocking layers can prevent adverseeffects on the elements formed over the peeling layer 1303 or theinsulating film 1304, which would otherwise be caused by an alkali metalsuch as Na or an alkaline earth metal contained in the substrate 1301 orby the impurity element contained in the peeling layer 1303. Note thatwhen quartz is used for the substrate 1301, the insulating films 1302and 1304 are not necessarily provided.

The peeling layer 1303 may be formed using, for example, a metal film ora stack-layer structure of a metal film and a metal oxide film. As ametal film, either a single layer or stack layer is formed using anelement selected from tungsten (W), molybdenum (Mo), titanium (Ti),tantalum (Ta), niobium (Nb), nickel (Ni), cobalt (Co), zirconium (Zr),zinc (Zn), ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os),and iridium (Ir), or an alloy material or a compound material containingany of those elements as its main component. In addition, the metal filmor the metal oxide film can be formed by a sputtering method, variousCVD methods such as a plasma CVD method. A stack-layer structure of ametal film and a metal oxide film can be obtained by, after forming theabove-described metal film, applying plasma treatment thereto under anoxygen atmosphere or an N₂O atmosphere or applying heat treatmentthereto under an oxygen atmosphere or an N₂O atmosphere; whereby oxideor oxynitride of the metal film can be formed on the surface of themetal film. For example, when a tungsten film is provided as a metalfilm by a sputtering method, a CVD method, or the like, a metal oxidefilm of tungsten oxide can be formed on the surface of the tungsten filmby application of plasma treatment to the tungsten film.

The amorphous semiconductor film 1305 is formed by a sputtering method,an LPCVD method, a plasma CVD method, or the like to have a thickness of25 to 200 nm (preferably, 30 to 150 nm).

Then, the amorphous semiconductor film 1305 is crystallized by beingirradiated with laser light. Alternatively, the amorphous semiconductorfilm 1305 may be crystallized by, for example, a method in which laserlight irradiation is combined with a thermal crystallization methodusing an RTA or an annealing furnace, or with a thermal crystallizationmethod using a metal element for promoting crystallization. After that,the obtained crystalline semiconductor film is etched to have desiredshapes, so that crystalline semiconductor films 1305 a to 1305 f areformed. Then, a gate insulating film 1306 is formed so as to cover thesemiconductor films 1305 a to 1305 f (see FIG. 18B).

The gate insulating film 1306 is formed of an insulating material suchas silicon oxide, silicon nitride, silicon oxynitride, or siliconnitride oxide, by a CVD method, a sputtering method, or the like. Forexample, when the gate insulating film 1306 has a two-layer structure, asilicon oxynitride film may be formed as a first insulating film and asilicon nitride oxide film may be formed as a second insulating film.Alternatively, a silicon oxide film may be formed as the firstinsulating film and a silicon nitride film may be formed as the secondinsulating film.

An example of a formation process of the crystalline semiconductor films1305 a to 1305 f is briefly described below. First, an amorphoussemiconductor film is formed by a plasma CVD method to have a thicknessof 50 to 60 nm. Then, a solution containing nickel, which is a metalelement for promoting crystallization, is retained on the amorphoussemiconductor film, and dehydrogenation treatment (at 500° C., for onehour) and thermal crystallization treatment (at 550° C., for four hours)are performed on the amorphous semiconductor film. Thus, a crystallinesemiconductor film is formed. After that, the crystalline semiconductorfilm is irradiated with laser light and is processed by aphotolithography method, so that the crystalline semiconductor films1305 a to 1305 f are formed. Note that, the amorphous semiconductor filmmay be crystallized only by laser light irradiation, not by thermalcrystallization using a metal element for promoting crystallization.

For a laser oscillator used for crystallization, either a continuouswave laser (a CW laser) or a pulsed wave laser (a pulsed laser) can beused. As a laser beam which can be used here, a laser beam emitted fromone or more of the following can be used: a gas laser such as an Arlaser, a Kr laser, or an excimer laser; a laser of which a medium issingle crystalline YAG, YVO₄, forsterite (Mg₂SiO₄), YAlO₃, GdVO₄, orpolycrystalline (ceramic) YAG, Y₂O₃, YVO₄, YAlO₃, or GdVO₄ doped withone or more of Nd, Yb, Cr, Ti, Ho, Er, Tm, and Ta as a dopant; a glasslaser; a ruby laser; an alexandrite laser; a Ti:sapphire laser; a coppervapor laser; and a gold vapor laser. Crystals with a large grain sizecan be obtained by irradiation with fundamental waves of such a laserbeam or second to fourth harmonics of the fundamental waves of such alaser beam. For example, the second harmonic (532 nm) or the thirdharmonic (355 nm) of an Nd:YVO4 laser (fundamental wave: 1064 nm) can beused. A power density of the laser in this case needs to be about 0.01to 100 MW/cm² (preferably, 0.1 to 10 MW/cm²) and the scanning rate forthe irradiation is set to be about 10 to 2000 cm/sec. Note that a laserof which a medium is single crystalline YAG, YVO₄, forsterite (Mg₂SiO₄),YAlO₃, or GdVO₄ or polycrystalline (ceramic) YAG, Y₂O₃, YVO₄, YAlO₃, orGdVO₄ doped with one or more of Nd, Yb, Cr, Ti, Ho, Er, Tm, and Ta as adopant; an Ar ion laser; or a Ti:sapphire laser can be used as a CWlaser, whereas such a laser can also be used as a pulsed laser with arepetition rate of 10 MHz or more by a Q-switch operation, mode locking,or the like. In the case where a laser beam with a reputation rate ofgreater than or equal to 10 MHz is used, a semiconductor film isirradiated with the next pulse after the semiconductor film is melted bythe laser and before it is solidified. Therefore, unlike the case ofusing a pulsed laser with a low repetition rate, a solid-liquidinterface can be continuously moved in the semiconductor film, so thatcrystal grains which grow continuously in a scanning direction can beobtained.

Alternatively, the gate insulating film 1306 may be formed by oxidizingor nitriding the surfaces of the crystalline semiconductor films 1305 ato 1305 f by performing the foregoing high-density plasma treatment. Forexample, the gate insulating film 1306 is formed by plasma treatment inwhich a mixed gas of a rare gas such as He, Ar, Kr, or Xe and oxygen,nitrogen oxide, ammonia, nitrogen, hydrogen or the like is introduced.When excitation of the plasma in this case is performed by introductionof a microwave, plasma with a low electron temperature and a highdensity can be generated. Surfaces of semiconductor films can beoxidized or nitrided by oxygen radicals (which may include OH radicals)or nitrogen radicals (which may include NH radicals) generated by thishigh-density plasma.

By the treatment using such high-density plasma, an insulating film isformed over the semiconductor films to have a thickness of 1 to 20 nm,typically 5 to 10 nm. Since the reaction in this case is a solid-phasereaction, the interface state density between the insulating film andthe semiconductor film can be quite low. Such high-density plasmatreatment directly oxidizes (or nitrides) a semiconductor film(crystalline silicon or polycrystalline silicon), variation in thicknessof the formed insulating film can be quite small, ideally. Further,crystal grain boundaries of crystalline silicon are not excessivelyoxidized, which makes a very preferable condition. In other words, bysolid-phase oxidation of a surface of the crystalline semiconductor filmby the high-density plasma treatment described here, an insulating filmwith good uniformity and low interface state density can be formedwithout excessive oxidation reaction at the crystal grain boundaries.

As the gate insulating film, an insulating film formed by high-densityplasma treatment may only be used, or an insulating film of siliconoxide, silicon oxynitride, silicon nitride, or the like may be depositedby a CVD method utilizing a plasma or thermal reaction and is stacked.In any case, transistors including insulating films formed byhigh-density plasma as a part of gate insulating films or as the gateinsulating films can have less variation in characteristics.

Further, the crystalline semiconductor films 1305 a to 1305 f, which areobtained by irradiating a semiconductor film with a continuous wavelaser beam or a laser beam oscillated with a repetition rate of greaterthan or equal to 10 MHz and scanning the semiconductor film with thelaser beam in one direction to crystallize the semiconductor film, havea characteristic such that the crystal grows in the scanning directionof the beam. When transistors are arranged so that the scanningdirection corresponds to their channel length direction (a direction inwhich carriers flow when a channel formation region is formed) and theforegoing gate insulating film is combined therewith, thin filmtransistors (TFTs) with less characteristic variation and high fieldeffect mobility can be obtained.

Next, a first conductive film and a second conductive film are formed tobe stacked over the gate insulating film 1306. Here, the firstconductive film is formed by a CVD method, a sputtering method, or thelike to have a thickness of 20 to 100 nm. The second conductive film isformed to have a thickness of 100 to 400 nm. The first and the secondconductive films are formed of an element selected from tantalum (Ta),tungsten (W), titanium (Ti), molybdenum (Mo), aluminum (Al), copper(Cu), chromium (Cr), niobium (Nb), and the like, or an alloy material ora compound material containing any of those elements as its maincomponent. Alternatively, the first and the second conductive films areformed of a semiconductor material typified by polycrystalline silicondoped with an impurity element such as phosphorus. As examples of acombination of the first conductive film and the second conductive film,a tantalum nitride film and a tungsten film, a tungsten nitride film anda tungsten film, a molybdenum nitride film and a molybdenum film, andthe like can be given. Since tungsten or tantalum nitride have high heatresistance, heat treatment for thermal activation can be performed afterthe formation of the first and the second conductive films. In addition,in the case of a three-layer structure instead of a two-layer structure,a stacked-layer structure including a molybdenum film, an aluminum film,and a molybdenum film may be employed.

Next, a mask formed of a resist is formed by a photolithography method,and etching treatment is performed for forming a gate electrode and agate wiring. Thus, gate electrodes 1307 are formed over the crystallinesemiconductor films 1305 a to 1305 f. Here, an example in which the gateelectrode 1307 has a stacked-layer structure including a firstconductive film 1307 a and a second conductive film 1307 b is described.

Next, the crystalline semiconductor films 1305 a to 1305 f are dopedwith an impurity element imparting n-type conductivity at lowconcentration by an ion doping method or an ion implantation method withthe use of the gate electrodes 1307 as masks. Then, a mask formed of aresist is formed selectively by a photolithography method, and animpurity element imparting p-type conductivity is added at highconcentration. As the n-type impurity element, phosphorus (P), arsenic(As), or the like can be used. As the p-type impurity element, boron(B), aluminum (Al), gallium (Ga), or the like can be used. Here,phosphorus (P) is used as the impurity element imparting n-typeconductivity and is selectively introduced into the crystallinesemiconductor films 1305 a to 1305 f so as to be contained with aconcentration of 1×10¹⁵ to 1×10¹⁹/cm³; thus, n-type impurity regions1308 are formed. Thus, boron (B) is used as the impurity elementimparting p-type conductivity and is selectively introduced into thecrystalline semiconductor films 1305 c and 1305 e so as to be containedwith a concentration of 1×10¹⁹ to 1×10²⁰/cm³; thus, p-type impurityregions 1309 are formed (see FIG. 18C).

Next, an insulating film is formed so as to cover the gate insulatingfilm 1306 and the gate electrodes 1307. The insulating film is formed tohave a single layer or stack layer of a film containing an inorganicmaterial such as silicon, oxide of silicon, or nitride of silicon, or afilm containing an organic material such as an organic resin, by aplasma CVD method, a sputtering method, or the like. Then, theinsulating film is selectively etched by anisotropic etching mainly inthe perpendicular direction, so that insulating films 1310 (alsoreferred to as side walls) which are in contact with side surfaces ofthe gate electrodes 1307 are formed. The insulating films 1310 are usedas masks in doping for forming lightly doped drain (LDD) regions.

Next, the crystalline semiconductor films 1305 a, 1305 b, 1305 d, and1305 f are doped with an impurity element imparting n-type conductivityat high concentration with the use of a mask formed of a resist by aphotolithography method, and the gate electrode 1307, and the insulatingfilms 1310 as masks. Thus, n-type impurity regions 1311 are formed.Here, phosphorus (P) is used as the impurity element imparting n-typeconductivity and is selectively introduced into the crystallinesemiconductor films 1305 a, 1305 b, 1305 d, and 1305 f so as to becontained with a concentration of 1×10¹⁹ to 1×10²⁰/cm³; thus, the n-typeimpurity regions 1311 with higher concentration of impurity than theimpurity regions 1308 are formed.

Through the foregoing steps, n-channel thin film transistors 1300 a,1300 b, 1300 d, and 1300 f, and p-channel thin film transistors 1300 cand 1300 e are formed (see FIG. 18D).

In the n-channel thin film transistor 1300 a, a channel formation regionis formed in a region in the crystalline semiconductor film 1305 a whichoverlaps with the gate electrode 1307, the impurity region 1311 forminga source region or a drain region is formed in a region which does notoverlap with the gate electrode 1307 and the insulating film 1310, and alightly doped drain region (LDD region) is formed in a region whichoverlaps with the insulating film 1310 and which is between the channelformation region and the impurity region 1311. Also in each of then-channel thin film transistors 1300 b, 1300 d, and 1300 f, a channelformation region, a lightly doped drain region, and the impurity region1311 are formed in a similar manner.

In the p-channel thin film transistor 1300 c, a channel formation regionis formed in a region in the crystalline semiconductor film 1305 c whichoverlaps with the gate electrode 1307, and the impurity region 1309forming a source region or a drain region is formed in a region whichdoes not overlap with the gate electrode 1307. Also in the p-channelthin film transistor 1300 e, a channel formation region and the impurityregion 1309 are formed in a similar manner. Note that although an LDDregion is not provided in the p-channel thin film transistors 1300 c and1300 e, the LDD region may be provided in the p-channel thin filmtransistor or the n-channel thin film transistor may have a structurewithout LDD regions.

Next, a single layer or stack layer of an insulating film is formed soas to cover the crystalline semiconductor films 1305 a to 1305 f, thegate electrodes 1307, and the like; and conductive films 1313 which areelectrically connected to the impurity regions 1309 and 1311 which farmsource regions or drain regions in the thin film transistors 1300 a to1300 f are formed over the insulating film (see FIG. 19A). Theinsulating film is formed to have a single layer or stack layer of aninorganic material such as oxide of silicon or nitride of silicon, anorganic material such as polyimide, polyamide, benzocyclobutene,acrylic, or epoxy, a siloxane material, or the like, by a CVD method, asputtering method, an SOG method, a droplet discharging method, a screenprinting method, or the like. Here, the insulating film has a two-layerstructure, in which a silicon nitride oxide film is formed as a firstinsulating film 1312 a, and a silicon oxynitride film is formed as asecond insulating film 1312 b. In addition, the conductive films 1313can form source electrodes or drain electrodes of the thin filmtransistors 1300 a to 1300 f.

Note that, before the insulating films 1312 a and 1312 b are formed orafter one or both of thin films of the insulating films 1312 a and 1312b are formed, heat treatment may be performed for recovering thecrystallinity of the semiconductor film, for activating the impurityelements which has been added into the semiconductor film, or forhydrogenating the semiconductor film As this heat treatment, thermalannealing, a laser annealing method, an RTA method, or the like may beemployed.

The conductive film 1313 is formed to have a single layer or stack layerof an element selected from, aluminum (Al), tungsten (W), titanium (Ti),tantalum (Ta), molybdenum (Mo), nickel (Ni), platinum (Pt), copper (Cu),gold (Au), silver (Ag), manganese (Mn), neodymium (Nd), carbon (C), andsilicon (Si), or an alloy material or a compound material containing anyof those elements as its main component by a CVD method, a sputteringmethod, or the like. An alloy material containing aluminum as its maincomponent corresponds to, for example, a material which containsaluminum as its main component and also contains nickel, or an alloymaterial which contains aluminum as its main component and which alsocontains nickel and one or both carbon and silicon. The conductive film1313 preferably employs, for example, a stack-layer structure includinga barrier film, an aluminum-silicon (Al—Si) film, and a barrier film, ora stack-layer structure including a barrier film, an aluminum-silicon(Al—Si) film, a titanium nitride film, and a barrier film. Note that thebarrier film refers to a thin film formed of titanium, nitride oftitanium, molybdenum, or nitride of molybdenum. Aluminum and aluminumsilicon have low resistance and are inexpensive; therefore, they areoptimal materials for forming the conductive film 1313. In addition,generation of a hillock of aluminum or aluminum silicon can be preventedwhen upper and lower barrier layers are formed. Furthermore, when thebarrier film is formed of titanium, which is an element with a highreducing property, even when a thin natural oxide film is formed on acrystalline semiconductor film, the natural oxide film can be reduced;so that preferable contact with the crystalline semiconductor film canbe obtained.

Next, an insulating film 1314 is formed so as to cover the conductivefilms 1313. And then, conductive films 1315 a and 1315 b to beelectrically connected to the conductive films 1313, which form thesource electrodes or drain electrodes of the thin film transistors 1300a and 1300 f are formed over the insulating film 1314. A conductive film1316 to be electrically connected to the conductive film 1313, whichforms the source electrode or drain electrode of the thin filmtransistor 1300 b is formed. Note that the conductive films 1315 a and1315 b and the conductive film 1316 may be formed of the same materialat the same time. The conductive films 1315 a and 1315 b and theconductive film 1316 can be formed of any of the foregoing materialswhich are given as materials for the conductive film 1313.

Next, a conductive film 1317 which serves as an antenna is formed so asto be electrically connected to the conductive film 1316 (see FIG. 19B).

The insulating film 1314 can be formed to have a single-layer orstack-layer structure of an insulating film containing oxygen and/ornitrogen such as silicon oxide (SiO_(x)), silicon nitride (SiN_(x)),silicon oxynitride (SiO_(x)N_(y)) (x>y), or silicon nitride oxide(SiN_(x)O_(y)) (x>y), a film containing carbon such as DLC (Diamond-LikeCarbon), a film of an organic material such as epoxy, polyimide,polyamide, polyvinyl phenol, benzocyclobutene, or acrylic, or a film ofa siloxane material such as a siloxane resin, which are formed by a CVDmethod, a sputtering method, or the like. Note that a siloxane materialrefers to a material including a Si—O—Si bond. Siloxane has a skeletonstructure containing a bond of silicon (Si) and oxygen (O). As asubstituent, an organic group containing at least hydrogen (e.g., analkyl group or aromatic hydrocarbon) is used. Alternatively, a fluorogroup can be used as the substituent. Further alternatively, both anorganic group containing at least hydrogen and a fluoro group may beused as the substituent.

The conductive film 1317 is formed of a conductive material by using aCVD method, a sputtering method, a printing method such as a screenprinting method or a gravure printing method, a droplet dischargingmethod, a dispensing method, a plating method, or the like. Theconductive material is an element selected from aluminum (Al), titanium(Ti), silver (Ag), copper (Cu), gold (Au), platinum (Pt), nickel (Ni),palladium (Pd), tantalum (Ta), and molybdenum (Mo), or an alloy materialor a compound material containing any of those elements as its maincomponent. The conductive film is formed to have a single-layer orstack-layer structure.

For example, in the case of forming the conductive film 1317 whichserves as the antenna by using a screen printing method, the conductivefilm 1317 can be provided by selectively printing a conductive paste inwhich conductive particles having a grain size of several nanometers toseveral tens of micrometers are dissolved or dispersed in an organicresin. As the conductive particles, metal particles of one or more ofsilver (Ag), gold (Au), copper (Cu), nickel (Ni), platinum (Pt),palladium (Pd), tantalum (Ta), molybdenum (Mo), titanium (Ti), and thelike, fine particles of silver halide, or dispersing nanoparticlesthereof can be used. In addition, as the organic resin contained in theconductive paste, one or more of organic resins selected from organicresins which serve as a binder, a solvent, a dispersing agent, and acoating member for the metal particles can be used. Typically, anorganic resin such as an epoxy resin or a silicone resin can be used.Further, in the formation of the conductive film, baking is preferablyperformed after the conductive paste is applied. For example, in thecase of using fine particles (with the grain size of, for example,greater or equal to 1 nm and less than or equal to 100 nm) containingsilver as its main component as a material for the conductive paste, theconductive paste is baked and hardened at temperatures of 150 to 300°C., so that the conductive film can be obtained. Alternatively, fineparticles containing solder or lead-free solder as its main componentmay be used; in that case, fine particles having a grain size of lessthan or equal to 20 μm are preferably used. Solder or lead-free solderhas advantages of low cost.

The conductive films 1315 a and 1315 b can serve as wirings which areelectrically connected to a secondary battery included in thesemiconductor device of the present invention in a later step. Inaddition, in forming the conductive film 1317 which serves as anantenna, other conductive films may be separately formed so as to beelectrically connected to the conductive films 1315 a and 1315 b and theconductive films can be utilized as the wirings for connecting theconductive films 1315 a and 1315 b to the secondary battery.

Next, an insulating film 1318 is formed so as to cover the conductivefilm 1317, after that, a layer including the thin film transistors 1300a to 1300 f, the conductive film 1317, and the like (hereinafter,referred to as an element formation layer 1319) is peeled off from thesubstrate 1301. Here, openings are formed by laser light (e.g., UVlight) irradiation in regions where the thin film transistors 1300 a to1300 f are not formed (see FIG. 19C), then, the element formation layer1319 can be peeled off from the substrate 1301 by physical force.Alternatively, an etchant may be introduced into the formed openings soas to selectively remove the separation layer 1303 before the elementformation layer 1319 is peeled off from the substrate 1301. As theetchant, gas or liquid containing halogen fluoride or an interhalogencompound is used. For example, when chlorine trifluoride (ClF₃) is usedas a gas containing halogen fluoride, the element formation layer 1319is peeled off from the substrate 1301. Note that the separation layer1303 may be partially left instead of being removed completely. Byleaving the separation layer 1303 partially, consumption of the etchantcan be reduced and the time for removing the separation layer can beshortened, as well as the element formation layer 1319 can be held overthe substrate 1301 even after the separation layer 1303 is removed.Further, the substrate 1301 is reused after the element formation layer1319 is peeled off; whereby cost can be reduced.

The insulating film 1318 can be formed to have a single-layer orstack-layer structure of an insulating film containing oxygen and/ornitrogen such as silicon oxide (SiO_(x)), silicon nitride (SiN_(x)),silicon oxynitride (SiO_(x)N_(y)) (x>y), or silicon nitride oxide(SiN_(x)O_(y)) (x>y), a film containing carbon such as DLC (Diamond-LikeCarbon), a film of an organic material such as epoxy, polyimide,polyamide, polyvinyl phenol, benzocyclobutene, or acrylic, or a film ofa siloxane material such as a siloxane resin by a CVD method, asputtering method, or the like.

In this embodiment mode, after the openings are formed in the elementformation layer 1319 by laser light irradiation, a first sheet material1320 is attached to one surface of the element formation layer 1319 (thesurface where the insulating film 1318 is exposed), and then, theelement formation layer 1319 is peeled off from the substrate 1301 (seeFIG. 20A).

Next, a second sheet material 1321 is provided on the other surface (thesurface exposed by peeling) of the element formation layer 1319, then,the second sheet material 1321 is attached to the surface by one or bothheat treatment and pressure treatment (see FIG. 20B). As the first sheetmaterial 1320 and the second sheet material 1321, a hot-melt film or thelike can be used.

As the first sheet material 1320 and the second sheet material 1321, afilm on which antistatic treatment for preventing static electricity orthe like is performed (hereinafter referred to as an antistatic film)can be used. As examples of the antistatic film, a film in which anantistatic material is dispersed in a resin, a film provided with anantistatic material attached thereon, or the like can be given. The filmprovided with an antistatic material may be a film provided with anantistatic material on one of its surfaces, or a film provided with anantistatic material on its opposing surfaces. As for the film providedwith an antistatic material on one of its surfaces, the film may beattached to the layer so that the antistatic material is placed on theinner side of the film or the outer side of the film. Note that theantistatic material may be provided on the entire surface of the film,or on a part thereof. As the antistatic material here, a metal, indiumtin oxide (ITO), a surfactant such as an amphoteric surfactant, acationic surfactant, or a nonionic surfactant can be used. Further, asan antistatic material, a resin material containing cross-linkedcopolymer having a carboxyl group and a quaternary ammonium base on itsside chain, or the like can be used. Such a material is attached, mixed,or applied to a film, to form an antistatic film. The element formationlayer is sealed using the antistatic film, so that the semiconductorelements can be protected from adverse effects such as external staticelectricity when being handled as a commercial product.

Note that a thin-film secondary battery is connected to the conductivefilms 1315 a and 1315 b, so that the storage capacitor of the powersupply circuit is formed. The connection with the secondary battery maybe made before the element formation layer 1319 is peeled off from thesubstrate 1301 (at the stage shown in FIG. 19B or FIG. 19C), after theelement formation layer 1319 is peeled off from the substrate 1301 (atthe stage shown in FIG. 20A), or after the element formation layer 1319is sealed with the first sheet material and the second sheet material(at the stage shown in FIG. 20B). An example in which the elementformation layer 1319 and the secondary battery are formed to beconnected is described below with reference to FIGS. 21A to 22B.

In FIG. 21A, conductive films 1331 a and 1331 b which are electricallyconnected to the conductive films 1315 a and 1315 b, respectively, areformed at the same time as the conductive film 1317 which serves as anantenna. Next, the insulating film 1318 is formed so as to cover theconductive film 1317 and the conductive films 1331 a and 1331 b. Then,openings 1332 a and 1332 b are formed so as to expose surfaces of theconductive films 1331 a and 1331 b. After that, the opening portions areformed in the element formation layer 1319 by laser irradiation, andthen the first sheet material 1320 is attached to one surface of theelement formation layer 1319 (the surface where the insulating film 1318is exposed), so that the element formation layer 1319 is peeled off fromthe substrate 1301 (see FIG. 21A).

Next, the second sheet material 1321 is attached to the other surface ofthe element formation layer 1319 (the surface exposed by peeling), andthe element formation layer 1319 is peeled off from the first sheetmaterial 1320. Therefore, a material with low viscosity is used as thefirst sheet material 1320. Then, conductive films 1334 a and 1334 bwhich are electrically connected to the conductive films 1331 a and 1331b, respectively through the opening 1332 a and 1332 b are selectivelyformed (see FIG. 21B).

The conductive films 1334 a and 1334 b are formed of a conductivematerial by a CVD method, a sputtering method, a printing method such asscreen printing or gravure printing, a droplet discharging method, adispenser method, a plating method, or the like. The conductive materialis any of the elements selected from aluminum (Al), titanium (Ti),silver (Ag), copper (Cu), gold (Au), platinum (Pt), nickel (Ni),palladium (Pd), tantalum (Ta), and molybdenum (Mo), or an alloy materialor a compound material containing any of those elements as its maincomponent. The conductive films are formed to have a single-layer orstacked-layer structure.

Although the example shown here is the case where the conductive films1334 a and 1334 b are formed after peeling the element formation layer1319 off from the substrate 1301, the element formation layer 1319 maybe peeled off from the substrate 1301 after the formation of theconductive films 1334 a and 1334 b.

Next, in the case where a plurality of elements are formed over thesubstrate, the element formation layer 1319 is cut into elements (seeFIG. 22A). A laser irradiation apparatus, a dicing apparatus, a scribingapparatus, or the like can be used for the cutting. At this time, theplurality of elements formed over one substrate are separated from oneanother by laser light irradiation.

Next, the separated elements are electrically connected to the secondarybattery (see FIG. 22B). In this embodiment mode, a thin-film secondarybattery is used as the storage capacitor of the power supply circuit, inwhich a current-collecting thin film, a negative electrode activematerial layer, a solid electrolyte layer, a positive electrode activematerial layer, and a current-collecting thin film are stacked in thisorder.

Conductive films 1336 a and 1336 b are formed of a conductive materialby a CVD method, a sputtering method, a printing method such as screenprinting or gravure printing, a droplet discharging method, a dispensermethod, a plating method, or the like. The conductive material is anelement selected from aluminum (Al), titanium (Ti), silver (Ag), copper(Cu), gold (Au), platinum (Pt), nickel (Ni), palladium (Pd), tantalum(Ta), and molybdenum (Mo), or an alloy material or a compound materialcontaining any of those elements as its main component. The conductivefilms are formed to have a single-layer or stack-layer structure. Theconductive material needs to have high adhesion to a negative electrodeactive substance as well as low resistance. In particular, aluminum,copper, nickel, vanadium, or the like is preferably used.

The structure of a thin-film secondary battery 1389 is described next. Anegative electrode active material layer 1381 is formed over theconductive film 1336 a. In general, vanadium oxide (V₂O₅) or the like isused. Next, a solid electrolyte layer 1382 is formed over the negativeelectrode active material layer 1381. In general, lithium phosphate(Li₃PO₄) or the like is used. Next, a positive electrode active materiallayer 1383 is formed over the solid electrolyte layer 1382. In general,lithium manganate (LiMn₂O₄) or the like is used. Lithium cobaltate(LiCoO₂) or lithium nickel oxide (LiNiO₂) may also be used. Next, acurrent-collecting thin film 1384 to serve as an electrode is Mimed overthe positive electrode active material layer 1383. Thecurrent-collecting thin film 1384 needs to have high adhesion to thepositive electrode active material layer 1383 as well as low resistance.For example, aluminum, copper, nickel, vanadium, or the like can beused.

Each of the above thin layers of the negative electrode active materiallayer 1381, the solid electrolyte layer 1382, the positive electrodeactive material layer 1383, and the current-collecting thin film 1384may be formed by a sputtering technique or an evaporation technique. Inaddition, the thickness of each layer is preferably 0.1 to 3 μm.

Next, an interlayer film 1385 is formed by application of a resin. Theinterlayer film is etched to form a contact hole. The interlayer film isnot limited to a resin, and another film such as a CVD oxide film may beused as well; however, a resin is preferably used in terms of flatness.Alternatively, the contact hole may be formed without using etching, butusing a photosensitive resin. Next, a wiring layer 1386 is formed overthe interlayer film and is connected to the conductive film 1336 b.Thus, an electrical connection between the thin-film secondary battery1389 and the elements is secured.

Here, the conductive films 1334 a and 1334 b which are provided in theelement formation layer 1319 are connected to the conductive films 1336a and 1336 b, which serve as connection terminals of the thin-filmsecondary battery 1389, respectively in advance. Here, an example isshown in which an electrical connection between the conductive films1334 a and 1336 a or an electrical connection between the conductivefilms 1334 b and 1336 b is performed by pressure bonding with anadhesive material such as an anisotropic conductive film (ACF) or ananisotropic conductive paste (ACP) therebetween. Here, an example isshown in which the connection is performed using conductive particles1338 included in an adhesive resin 1337. Alternatively, a conductiveadhesive such as a silver paste, a copper paste, or a carbon paste;solder joint; or the like can be used for the connection.

The structures of such transistors can be various and is not limited tothe specific structures shown in this embodiment mode. For example, amulti-gate structure having two or more gate electrodes may be employed.When a multi-gate structure is employed, a structure in which channelregions are connected in series is provided; therefore, a structure inwhich a plurality of transistors are connected in series is provided.When a multi-gate structure is employed for the transistor, off-currentcan be reduced; withstand voltage of the transistor can be increased, sothat the reliability is increased; and even if drain-source voltagechanges when the transistor operates in the saturation region, adrain-source current does not change very much, and thus flatcharacteristics can be obtained. Further, a structure in which gateelectrodes are formed above and below a channel may also be employed.When the structure in which gate electrodes are provided above and belowa channel is employed, the channel region is enlarged and the amount ofcurrent flowing therethrough can be increased. Thus, a depletion layercan be easily formed and the subthreshold swing can be decreased. Whengate electrodes are formed above and below a channel, a structure inwhich a plurality of transistors are connected in parallel is made.

Alternatively, the transistor may have any of the following structures:a structure in which a gate electrode is provided above a channel, astructure in which a gate electrode is provided below a channel, astaggered structure, and an inverted staggered structure. Furtheralternatively, a structure in which a channel region is divided into aplurality of regions and the divided channel regions are connected inparallel or in series. In addition, a channel (or a part thereof) mayoverlap with a source electrode or a drain electrode. When a structurein which a channel (or a part thereof) overlaps with a source electrodeor a drain electrode is employed, electric charges can be prevented frombeing accumulated in a part of the channel and thus an unstableoperation can be prevented. Further, an LDD region may be provided. Whenan LDD region is provided, off-current can be reduced; the withstandvoltage of the transistor can be increased, so that the reliability isincreased; and even if drain-source voltage changes when the transistoroperates in the saturation region, drain-source current does not changevery much, and thus flat characteristics can be obtained.

Note that a method of manufacturing a semiconductor device in thisembodiment mode can be applied to a semiconductor device in anotherembodiment mode described in this specification.

Embodiment Mode 5

In this embodiment mode, an example of a method of manufacturing asemiconductor device described in any of the foregoing embodiment modesis described with reference to drawing. This embodiment mode describes astructure in which a communication control circuit, a rectifier circuit,a charge control circuit, and the like in the semiconductor device areformed over one substrate. Note that the communication control circuit,the rectifier circuit, the charge control circuit, and the like in thesemiconductor device are formed at a time over the substrate usingtransistors including channel formation regions formed using a singlecrystalline substrate. When transistors formed using a singlecrystalline substrate are used as the transistors, a semiconductordevice having transistors with few characteristic variations can beformed, which is preferable. In addition, this embodiment mode describesan example in which the thin-film secondary battery described inEmbodiment Mode 4 is used as a battery.

First, an insulating film (also referred to as a field oxide film) 2302is formed on a semiconductor substrate 2300 to separate regions (alsoreferred to as element formation regions or element separation regions)2304 and 2306 (see FIG. 11A). The regions 2304 and 2306 provided in thesemiconductor substrate 2300 are insulated from each other by theinsulating film 2302. The example shown here is the case where a singlecrystal Si substrate having n-type conductivity is used as thesemiconductor substrate 2300, and a p-well 2307 is formed in the region2306 in the semiconductor substrate 2300.

Any substrate can be used as the semiconductor substrate 2300 as long asit is a semiconductor substrate. For example, a single crystal Sisubstrate having n-type or p-type conductivity, a compound semiconductorsubstrate (e.g., a GaAs substrate, an InP substrate, a GaN substrate, aSiC substrate, a sapphire substrate, or a ZnSe substrate), an SOI(silicon on insulator) substrate formed by a bonding method or a SIMOX(separation by implanted oxygen) method, or the like can be used.

The regions 2304 and 2306 can be formed by appropriately using a localoxidation of silicon (LOCOS) method, a trench isolation method, or thelike.

In addition, the p-well formed in the region 2306 in semiconductorsubstrate 2300 can be formed by selective doping of the semiconductorsubstrate 2300 with a p-type impurity element. As a p-type impurityelement, boron (B), aluminum (Al), gallium (Ga), or the like can beused.

In this embodiment mode, although the region 2304 is not doped with animpurity element because a semiconductor substrate having n-typeconductivity is used as the semiconductor substrate 2300, an n-well maybe formed in the region 2304 by doping with an n-type impurity element.As an n-type impurity element, phosphorus (P), arsenic (As), or the likecan be used. When a semiconductor substrate having p-type conductivityis used, on the other hand, the region 2304 may be doped with an n-typeimpurity element to form an n-well, whereas the region 2306 may be dopedwith no impurity element.

Next, insulating films 2332 and 2334 are formed so as to cover theregions 2304 and 2306, respectively (see FIG. 11B).

For example, surfaces of the regions 2304 and 2306 provided in thesemiconductor substrate 2300 are oxidized by heat treatment, so that theinsulating films 2332 and 2334 can be formed of silicon oxide films.Alternatively, the insulating films may be formed to have a stack-layerstructure of a silicon oxide film and a film containing oxygen andnitrogen (a silicon oxynitride film) by forming a silicon oxide film bya thermal oxidation method and then nitriding the surface of the siliconoxide film by nitridation treatment.

Further alternatively, the insulating films 2332 and 2334 may be formedby plasma treatment as described above. For example, the insulatingfilms 2332 and 2334 can be formed using a silicon oxide (SiO_(x)) filmor a silicon nitride (SiN_(x)) film which is obtained by application ofoxidation or nitridation treatment using high-density plasma to thesurfaces of the regions 2304 and 2306 provided in the semiconductorsubstrate 2300. Furthermore, after applying oxidation treatment usinghigh-density plasma to the surfaces of the regions 2304 and 2306,nitridation treatment using high-density plasma may be performed. Inthat case, silicon oxide films are formed on the surfaces of the regions2304 and 2306, and then silicon oxynitride films are formed on thesilicon oxide films. Thus, the insulating films 2332 and 2334 are eachformed to have a stack-layer structure including the silicon oxide filmand the silicon oxynitride film. After the silicon oxide films areformed on the surfaces of the regions 2304 and 2306 by a thermaloxidation method, oxidation or nitridation treatment using high-densityplasma may be applied to the silicon oxide films.

The insulating films 2332 and 2334 formed over the regions 2304 and 2306in the semiconductor substrate 2300 serve as the gate insulating filmsof transistors which are completed later.

Next, a conductive film is formed so as to cover the insulating films2332 and 2334, which are formed over the regions 2304 and 2306,respectively (see FIG. 11C). Here, an example is shown in which theconductive film is formed by sequentially stacking conductive films 2336and 2338. Needless to say, the conductive film may be formed to have asingle layer or a stack-layer structure of three or more layers.

As materials of the conductive films 2336 and 2338, an element selectedfrom tantalum (Ta), tungsten (W), titanium (Ti), molybdenum (Mo),aluminum (Al), copper (Cu), chromium (Cr), niobium (Nb), and the like,or an alloy material or a compound material containing any of thoseelements as its main component can be used. Alternatively, a metalnitride film obtained by nitridation of any of those elements can beused. Further alternatively, a semiconductor material typified bypolycrystalline silicon doped with an impurity element such asphosphorus can be used.

Here, a stack-layer structure is provided including the conductive film2336 formed using tantalum nitride and the conductive film 2338 formedthereon using tungsten. Alternatively, the conductive film 2336 can beformed to have a single-layer or stack-layer film using any of tungstennitride, molybdenum nitride, or titanium nitride, and the conductivefilm 2338 can be formed to have a single-layer or stack-layer film usingany of tungsten, tantalum, molybdenum, or titanium.

Next, the stacked conductive films 2336 and 2338 are selectively removedby etching, so that the conductive films 2336 and 2338 remain aboveparts of the regions 2304 and 2306. Thus, gate electrodes 2340 and 2342are fowled (see FIG. 12A).

Next, a resist mask 2348 is selectively formed so as to cover the region2304, and the region 2306 is doped with an impurity element, using theresist mask 2348 and the gate electrode 2342 as masks, so that impurityregions are formed (see FIG. 12B). As an impurity element, an n-typeimpurity element or a p-type impurity element is used. As an n-typeimpurity element, phosphorus (P), arsenic (As), or the like can be used.As a p-type impurity element, boron (B), aluminum (Al), gallium (Ga), orthe like can be used. Here, phosphorus (P) is used as the impurityelement.

In FIG. 12B, by doping with an impurity element, impurity regions 2352which form source and drain regions and a channel formation region 2350are formed in the region 2306.

Next, a resist mask 2366 is selectively formed so as to cover the region2306, and the region 2304 is doped with an impurity element, using theresist mask 2366 and the gate electrode 2340 as masks, so that impurityregions are formed (see FIG. 12C). As the impurity element, an n-typeimpurity element or a p-type impurity element is used. As an n-typeimpurity element, phosphorus (P), arsenic (As), or the like can be used.As a p-type impurity element, boron (B), aluminum (Al), gallium (Ga), orthe like can be used. Here, an impurity element (e.g., boron (B)) of aconductivity type different from that of the impurity element introducedinto the region 2306 in FIG. 12B is used. As a result, impurity regions2370 which form source and drain regions and a channel formation region2368 are formed in the region 2304.

Next, a second insulating film 2372 is formed so as to cover theinsulating films 2332 and 2334 and the gate electrodes 2340 and 2342.Then, wiring 2374, which are electrically connected to the impurityregions 2352 and 2370 formed in the regions 2306 and 2304 respectively,are formed over the second insulating film 2372 (see FIG. 13A).

The second insulating film 2372 can be formed to have a single-layer orstack-layer structure of an insulating film containing oxygen and/ornitrogen such as silicon oxide (SiO_(x)), silicon nitride (SiN_(x)),silicon oxynitride (SiO_(x)N_(y)) (x>y), or silicon nitride oxide(SiN_(x)O_(y)) (x>y), a film containing carbon such as DLC (Diamond-LikeCarbon), a film of an organic material such as epoxy, polyimide,polyamide, polyvinyl phenol, benzocyclobutene, or acrylic, or a film ofa siloxane material such as a siloxane resin, which are formed by a CVDmethod, a sputtering method, or the like. Note that a siloxane materialrefers to a material including a Si—O—Si bond. Siloxane has a skeletonstructure containing a bond of silicon (Si) and oxygen (O). As asubstituent, an organic group containing at least hydrogen (e.g., analkyl group or aromatic hydrocarbon) is used. Alternatively, a fluorogroup can be used as the substituent. Further alternatively, both anorganic group containing at least hydrogen and a fluoro group may beused as the substituent.

The wiring 2374 is formed to have a single layer or stack layer of anelement selected from, aluminum (Al), tungsten (W), titanium (Ti),tantalum (Ta), molybdenum (Mo), nickel (Ni), platinum (Pt), copper (Cu),gold (Au), silver (Ag), manganese (Mn), neodymium (Nd), carbon (C), andsilicon (Si), or an alloy material or a compound material containing anyof those elements as its main component by a CVD method, a sputteringmethod, or the like. An alloy material containing aluminum as its maincomponent corresponds to, for example, a material which containsaluminum as its main component and also contains nickel, or an alloymaterial which contains aluminum as its main component and which alsocontains nickel and one or both carbon and silicon. The wiring 2374preferably employs, for example, a stack-layer structure including abarrier film, an aluminum-silicon (Al—Si) film, and a barrier film, or astack-layer structure including a barrier film, an aluminum-silicon(Al—Si) film, a titanium nitride film, and a barrier film. Note that thebarrier film refers to a thin film formed of titanium, nitride oftitanium, molybdenum, or nitride of molybdenum. Aluminum and aluminumsilicon have low resistance and are inexpensive; therefore, they areoptimal materials for forming the wiring 2374. In addition, generationof a hillock of aluminum or aluminum silicon can be prevented when upperand lower barrier layers are formed. Furthermore, when the barrier filmis formed of titanium, which is an element with a high reducingproperty, even when a thin natural oxide film is formed on a crystallinesemiconductor film, the natural oxide film can be reduced; so thatpreferable contact with the crystalline semiconductor film can beobtained.

Note that the structure of transistors of the present invention is notlimited to the one shown in drawings. For example, a transistor with aninverted staggered structure, a FinFET structure, or the like can beused. A FinFET structure is preferable because it can suppress a shortchannel effect which occurs along with reduction in transistor size.

In this embodiment mode, the secondary battery is stacked over thewiring 2374 connected to the transistor. The secondary battery has astructure in which a current-collecting thin film, a negative electrodeactive material layer, a solid electrolyte layer, a positive electrodeactive material layer, and a current-collecting thin film aresequentially stacked (see FIG. 13B). Therefore, the material of thewiring 2374, which also serve as the current-collecting thin film of thesecondary battery, needs to have high adhesion to the negative electrodeactive material layer as well as low resistance. In particular,aluminum, copper, nickel, vanadium, or the like is preferably used.

The structure of a thin-film secondary battery is described next. Anegative electrode active material layer 2391 is formed over the wiring2374. In general, vanadium oxide (V₂O₅) or the like is used. Next, asolid electrolyte layer 2392 is formed over the negative electrodeactive material layer 2391. In general, lithium phosphate (Li₃PO₄) orthe like is used. Next, a positive electrode active material layer 2393is formed over the solid electrolyte layer 2392. In general, lithiummanganate (LiMn₂O₄) or the like is used. Lithium cobaltate (LiCoO₂) orlithium nickel oxide (LiNiO₂) may also be used. Next, acurrent-collecting thin film 2394 to serve as an electrode is formedover the positive electrode active material layer 2393. Thecurrent-collecting thin film 2394 needs to have high adhesion to thepositive electrode active material layer 2393 as well as low resistance.For example, aluminum, copper, nickel, vanadium, or the like can beused.

Each of the above thin layers of the negative electrode active materiallayer 2391, the solid electrolyte layer 2392, the positive electrodeactive material layer 2393, and the current-collecting thin film 2394may be formed by a sputtering technique or an evaporation technique. Inaddition, the thickness of each layer is preferably 0.1 to 3 μm.

Next, an interlayer film 2396 is formed by application of a resin. Theinterlayer film 2396 is etched to form a contact hole. The interlayerfilm is not limited to a resin, and another film such as a CVD oxidefilm may be used as well; however, a resin is preferably used in termsof flatness. Alternatively, the contact hole may be formed without usingetching, but using a photosensitive resin. Next, a wiring layer 2395 isformed over the interlayer film 2396 and is connected to a wiring 2397.Thus, an electrical connection between the thin-film secondary batteryand an element (transistor) is secured.

With the foregoing structure, the semiconductor device of the presentinvention can have a structure in which transistors are formed using asingle crystalline substrate and a thin-film secondary battery is formedthereover. Therefore, the semiconductor device of the present inventioncan achieve flexibility as well as thinning and reduction in size.

Note that a method of manufacturing a semiconductor device in thisembodiment mode can be applied to a semiconductor device in anotherembodiment mode described in this specification.

Embodiment Mode 6

In this embodiment mode, a method of manufacturing a semiconductordevice, which is different from that of Embodiment Mode 5 is describedwith reference to drawings.

First, an insulating film is formed over a substrate 2600. Here, asingle crystal Si substrate having n-type conductivity is used as thesubstrate 2600, and insulating films 2602 and 2604 are formed over thesubstrate 2600 (see FIG. 14A). For example, a film of silicon oxide(SiO_(x)) is formed as the insulating film 2602 by application of heattreatment to the substrate 2600, and then a film of silicon nitride(SiN_(x)) is fowled over the insulating film 2602 by a CVD method.

Any substrate can be used as the substrate 2600 as long as it is asemiconductor substrate. For example, a single crystal Si substratehaving n-type or p-type conductivity, a compound semiconductor substrate(e.g., a GaAs substrate, an InP substrate, a GaN substrate, a SiCsubstrate, a sapphire substrate, or a ZnSe substrate), an SOI (siliconon insulator) substrate formed by a bonding method or a SIMOX(separation by implanted oxygen) method, or the like can be used.

Alternatively, after forming the insulating film 2602, the insulatingfilm 2604 may be formed by nitridation of the insulating film 2602 byhigh-density plasma treatment. Note that the insulating film providedover the substrate 2600 may have a single-layer or stack-layer structureof three or more layers.

Next, patterns of a resist mask 2606 are selectively formed over theinsulating film 2604, and selective etching is performed using theresist mask 2606 as a mask, so that depressions 2608 are selectivelyformed in the substrate 2600 (see FIG. 14B). For the etching of thesubstrate 2600 and the insulating films 2602 and 2604, dry etching canbe carried out using plasma.

Next, the patterns of the resist mask 2606 are removed, and then aninsulating film 2610 is formed so as to fill the depressions 2608 formedin the substrate 2600 (see FIG. 14C).

The insulating film 2610 is formed of an insulating material such assilicon oxide, silicon nitride, silicon oxynitride (SiO_(x)N_(y), wherex>y), or silicon nitride oxide (SiN_(x)O_(y), where x>y) by a CVDmethod, a sputtering method, or the like. Here, as the insulating film2610, a silicon oxide film is formed by an atmospheric pressure CVDmethod or a low-pressure CVD method using a TEOS (tetraethylorthosilicate) gas.

Next, the surface of the substrate 2600 is exposed by grinding treatmentor polishing treatment such as CMP (Chemical Mechanical Polishing).Here, by exposure of the surface of the substrate 2600, regions 2612 and2613 are formed between insulating films 2611 which are formed in thedepressions 2608 of the substrate 2600. Note that the insulating films2611 are obtained by removing the insulating film 2610 which is formedover the surface of the substrate 2600 by grinding treatment orpolishing treatment such as CMP. Then, by selective doping with a p-typeimpurity element, a p-well 2615 is formed in the region 2613 of thesubstrate 2600 (see FIG. 15A).

As a p-type impurity element, boron (B), aluminum (Al), gallium (Ga), orthe like can be used. Here, boron (B) is introduced into the region 2613as the impurity element.

In this embodiment mode, although the region 2612 is not doped with animpurity element because a semiconductor substrate having n-typeconductivity is used as the substrate 2600, an n-well may be formed inthe region 2612 by doping with an n-type impurity element. As an n-typeimpurity element, phosphorus (P), arsenic (As), or the like can be used.

When a semiconductor substrate having p-type conductivity is used, onthe other hand, the region 2612 may be doped with an n-type impurityelement to form an n-well, whereas the region 2613 may be doped with noimpurity element.

Next, insulating films 2632 and 2634 are formed so as to cover theregions 2612 and 2613, respectively in the substrate 2600 (see FIG.15B).

For example, surfaces of the regions 2612 and 2613 provided in thesubstrate 2600 are oxidized by heat treatment, so that the insulatingfilms 2632 and 2634 can be formed of silicon oxide films. Alternatively,the insulating films may be formed to have a stack-layer structure of asilicon oxide film and a film containing oxygen and nitrogen (a siliconoxynitride film) by forming a silicon oxide film by a thermal oxidationmethod and then nitriding the surface of the silicon oxide film bynitridation treatment.

Further alternatively, the insulating films 2632 and 2634 may be formedby plasma treatment as described above. For example, the insulatingfilms 2632 and 2634 can be formed using a silicon oxide (SiO_(x)) filmor a silicon nitride (SiN_(x)) film which is obtained by application ofoxidation or nitridation treatment using high-density plasma treatmentto the surfaces of the regions 2612 and 2613 provided in the substrate2600. Furthermore, after applying oxidation treatment using high-densityplasma to the surfaces of the regions 2612 and 2613, nitridationtreatment using high-density plasma may be performed. In that case,silicon oxide films are formed on the surfaces of the regions 2612 and2613, and then silicon oxynitride films are formed on the silicon oxidefilms. Thus, the insulating films 2632 and 2634 are each formed to havea stack-layer structure including the silicon oxide film and the siliconoxynitride film. After the silicon oxide films are formed on thesurfaces of the regions 2612 and 2613 by a thermal oxidation method,oxidation or nitridation treatment using high-density plasma may beapplied to the silicon oxide films.

The insulating films 2632 and 2634 formed over the regions 2612 and 2613in the substrate 2600 serve as the gate insulating films of transistorswhich are completed later.

Next, a conductive film is formed so as to cover the insulating films2632 and 2634, which are formed over the regions 2612 and 2613 providedin the substrate 2600, respectively (see FIG. 15C). Here, an example isshown in which the conductive film is formed by sequentially stackingconductive films 2636 and 2638. Needless to say, the conductive film maybe formed to have a single layer or a stack-layer structure of three ormore layers.

As materials of the conductive films 2636 and 2638, an element selectedfrom tantalum (Ta), tungsten (W), titanium (Ti), molybdenum (Mo),aluminum (Al), copper (Cu), chromium (Cr), niobium (Nb), and the like,or an alloy material or a compound material containing any of thoseelements as its main component can be used. Alternatively, a metalnitride film obtained by nitridation of any of those elements can beused. Further alternatively, a semiconductor material typified bypolycrystalline silicon doped with an impurity element such asphosphorus can be used.

Here, a stack-layer structure is provided including the conductive film2636 formed using tantalum nitride and the conductive film 2638 formedthereon using tungsten. Alternatively, the conductive film 2636 can beformed to have a single-layer or stack-layer film using any of tantalumnitride, tungsten nitride, molybdenum nitride, or titanium nitride, andthe conductive film 2638 can be formed to have a single-layer orstack-layer film using any of tungsten, tantalum, molybdenum, ortitanium.

Next, the stacked conductive films 2636 and 2638 are selectively removedby etching, so that the conductive films 2636 and 2638 remain aboveparts of the regions 2612 and 2613 in the substrate 2600. Thus,conductive films 2640 and 2642 each of which serves as a gate electrodeare formed (see FIG. 16A). Here, surfaces of the regions 2612 and 2613of the substrate 2600 which do not overlap with the conductive films2640 and 2642 respectively are exposed.

Specifically, in the region 2612 in the substrate 2600, a part of theinsulating film 2632 which is formed below the conductive film 2640 anddoes not overlap with the conductive film 2640, is selectively removed,so that the ends of the conductive film 2640 and the ends of theinsulating film 2632 are almost aligned with each other. In addition, inthe region 2613 in the substrate 2600, a part of the insulating film2634 which is formed below the conductive film 2642 and does not overlapwith the conductive film 2642, is selectively removed, so that the endsof the conductive film 2642 and the ends of the insulating film 2634 arealmost aligned with each other.

In this case, the part of the insulating films or the like which do notoverlap with the conductive films 2640 and 2642 may be removed at thesame time as the formation of the conductive films 2640 and 2642.Alternatively, the part of the insulating films which do not overlapwith the conductive films 2640 and 2642 may be removed using resistmasks which are left after the formation of the conductive films 2640and 2642 or using the conductive films 2640 and 2642 as masks.

Next, the regions 2612 and 2613 in the substrate 2600 are doped with animpurity element (see FIG. 16B). Here, the region 2613 is selectivelydoped with an n-type impurity element at low concentration, using theconductive film 2642 as a mask, to form low concentration impurityregions 2650, whereas the region 2612 is selectively doped with a p-typeimpurity element at low concentration, using the conductive film 2640 asa mask, to form low concentration impurity regions 2648. As an n-typeimpurity element, phosphorus (P), arsenic (As), or the like can be used.As a p-type impurity element, boron (B), aluminum (Al), gallium (Ga), orthe like can be used.

Next, sidewalls 2654 are formed so as to be in contact with the sidesurfaces of the conductive films 2640 and 2642. Specifically, theinsulating film is fowled to have a single layer or stack layer of afilm containing an inorganic material such as silicon, oxide of silicon,or nitride of silicon, or a film containing an organic material such asan organic resin, by a plasma CVD method, a sputtering method, or thelike. Then, the insulating film is selectively etched by anisotropicetching mainly in the perpendicular direction, so that the sidewalls2654 which are in contact with side surfaces of the conductive films2640 and 2642 are formed. The sidewalls 2654 are used as masks in dopingfor forming lightly doped drain (LDD) regions. In addition, thesidewalls 2654 are formed to be in contact with side surfaces of theinsulating films formed below the conductive films 2640 and 2642.

Next, the regions 2612 and 2613 in the substrate 2600 are doped with animpurity element, using the sidewalls 2654 and the conductive films 2640and 2642 as masks, so that impurity regions which serve as source anddrain regions are formed (see FIG. 16C). At this time, the region 2613in the substrate 2600 is doped with an n-type impurity element at highconcentration, using the sidewalls 2654 and the conductive film 2642 asmasks, whereas the region 2612 is doped with a p-type impurity elementat high concentration, using the sidewalls 2654 and the conductive film2640 as masks.

In this manner, impurity regions 2658 which form source and drainregions, low concentration impurity regions 2660 which form LDD regions,and a channel formation region 2656 are formed in the region 2612 in thesubstrate 2600. Meanwhile, impurity regions 2664 which form source anddrain regions, low concentration impurity regions 2666 which form LDDregions, and a channel formation region 2662 are formed in the region2613 in the substrate 2600.

In this embodiment mode, the impurity elements are introduced under thecondition in which parts of the regions 2612 and 2613 in the substrate2600 which do not overlap with the conductive films 2640 and 2642 areexposed. Accordingly, the channel formation regions 2656 and 2662 whichare formed in the regions 2612 and 2613 in the substrate 2600,respectively, can be formed in a self-aligned manner, due to theconductive films 2640 and 2642.

Next, an insulating film 2677 is formed so as to cover the insulatingfilms, the conductive films, and the like which are provided over theregions 2612 and 2613 of the substrate 2600, and opening portions 2678are formed in the insulating film 2677 (see FIG. 17A).

The insulating film 2677 can be formed to have a single-layer orstack-layer structure of an insulating film containing oxygen and/ornitrogen such as silicon oxide (SiO_(x)), silicon nitride (SiN_(x)),silicon oxynitride (SiO_(x)N_(y)) (x>y), or silicon nitride oxide(SiN_(x)O_(y)) (x>y), a film containing carbon such as DLC (Diamond-LikeCarbon), a film of an organic material such as epoxy, polyimide,polyamide, polyvinyl phenol, benzocyclobutene, or acrylic, or a film ofa siloxane material such as a siloxane resin, which are formed by a CVDmethod, a sputtering method, or the like. Note that a siloxane materialrefers to a material including a Si—O—Si bond. Siloxane has a skeletonstructure containing a bond of silicon (Si) and oxygen (O). As asubstituent, an organic group containing at least hydrogen (e.g., analkyl group or aromatic hydrocarbon) is used. Alternatively, a fluorogroup can be used as the substituent. Further alternatively, both anorganic group containing at least hydrogen and a fluoro group may beused as the substituent.

Next, conductive films 2680 are formed in the opening portions 2678 by aCVD method and conductive films 2682 a to 2682 d are selectively formedover the insulating film 2677 so as to be electrically connected to theconductive films 2680 (see FIG. 17B).

The conductive films 2680 and 2682 a to 2682 d are formed to have asingle layer or stack layer of an element selected from, aluminum (Al),tungsten (W), titanium (Ti), tantalum (Ta), molybdenum (Mo), nickel(Ni), platinum (Pt), copper (Cu), gold (Au), silver (Ag), manganese(Mn), neodymium (Nd), carbon (C), and silicon (Si), or an alloy materialor a compound material containing any of those elements as its maincomponent by a CVD method, a sputtering method, or the like. An alloymaterial containing aluminum as its main component corresponds to, forexample, a material which contains aluminum as its main component andalso contains nickel, or an alloy material which contains aluminum asits main component and which also contains nickel and one or both carbonand silicon. The conductive films 2680 and 2682 a to 2682 d preferablyemploy, for example, a stack-layer structure including a barrier film,an aluminum-silicon (Al—Si) film, and a barrier film, or a stack-layerstructure including a barrier film, an aluminum-silicon (Al—Si) film, atitanium nitride film, and a barrier film. Note that the barrier filmrefers to a thin film formed of titanium, nitride of titanium,molybdenum, or nitride of molybdenum. Aluminum and aluminum silicon havelow resistance and are inexpensive; therefore, they are optimalmaterials for forming the conductive films 2680 and 2682 a to 2682 d. Inaddition, generation of a hillock of aluminum or aluminum silicon can beprevented when upper and lower barrier layers are formed. Furthermore,in the case where the barrier film is formed by using titanium, which isan element with a high reducing property, even when a thin natural oxidefilm is formed on a crystalline semiconductor film, the natural oxidefilm can be reduced; so that preferable contact with the crystallinesemiconductor film can be obtained. Here, the conductive film 2680 and2682 a to 2682 d can be formed by selectively growing tungsten (W) by aCVD method.

Through the foregoing steps, a p-channel thin film transistor and ann-channel thin film transistor formed in the regions 2612 and 2613 inthe substrate 2600, respectively can be obtained.

Note that the structure of transistors of the present invention is notlimited to the one shown in drawings. For example, a transistor with aninverted staggered structure, a FinFET structure, or the like can beused. A FinFET structure is preferable because it can suppress a shortchannel effect which occurs along with reduction in transistor size.

In this embodiment mode, the secondary battery is stacked over theconductive film 2682 d connected to the transistor. The secondarybattery has a structure in which a current-collecting thin film, anegative electrode active material layer, a solid electrolyte layer, apositive electrode active material layer, and a current-collecting thinfilm are sequentially stacked (see FIG. 17B). Therefore, the material ofthe conductive film 2682 d, which also serve as the current-collectingthin film of the secondary battery, needs to have high adhesion to thenegative electrode active material layer as well as low resistance. Inparticular, aluminum, copper, nickel, vanadium, or the like ispreferably used.

The structure of a thin-film secondary battery is described next. Anegative electrode active material layer 2691 is formed over theconductive film 2682 d. In general, vanadium oxide (V₂O₅) or the like isused. Next, a solid electrolyte layer 2692 is formed over the negativeelectrode active material layer 2691. In general, lithium phosphate(Li₃PO₄) or the like is used. Next, a positive electrode active materiallayer 2693 is formed over the solid electrolyte layer 2392. In general,lithium manganate (LiMn₂O₄) or the like is used. Lithium cobaltate(LiCoO₂) or lithium nickel oxide (LiNiO₂) may also be used. Next, acurrent-collecting thin film 2694 to serve as an electrode is formedover the positive electrode active material layer 2693. Thecurrent-collecting thin film 2694 needs to have high adhesion to thepositive electrode active material layer 2693 as well as low resistance.For example, aluminum, copper, nickel, vanadium, or the like can beused.

Each of the above thin layers of the negative electrode active materiallayer 2691, the solid electrolyte layer 2692, the positive electrodeactive material layer 2693, and the current-collecting thin film 2694may be formed by a sputtering technique or an evaporation technique. Inaddition, the thickness of each layer is preferably 0.1 to 3 μm.

Next, an interlayer film 2696 is formed by application of a resin. Theinterlayer film 2696 is etched to form a contact hole. The interlayerfilm 2696 is not limited to a resin, and another film such as a CVDoxide film may be used as well; however, a resin is preferably used interms of flatness. Alternatively, the contact hole may be formed withoutusing etching, but using a photosensitive resin. Next, a wiring layer2695 is formed over the interlayer film 2696 and is connected to awiring 2697. Thus, an electrical connection of the thin-film secondarybattery is secured.

With the foregoing structure, the semiconductor device of the presentinvention can have a structure in which transistors are formed using asingle crystalline substrate and a thin-film secondary battery is formedthereover. Therefore, the semiconductor device of the present inventioncan achieve flexibility as well as thinning and reduction in size.

Note that a method of manufacturing a semiconductor device in thisembodiment mode can be applied to a semiconductor device in anotherembodiment mode described in this specification.

Embodiment Mode 7

In this embodiment, uses of an RFID tag, which is an example of a usagemode of a semiconductor device which is capable of transmitting andreceiving information wirelessly is described. An RFID tag can beincluded in, for example, bills, coins, securities, bearer bonds,documents (e.g., driver's licenses or resident's cards), packagingcontainers (e.g., wrapping paper or bottles), storage media (e.g., DVDsoftware or video tapes), vehicles (e.g., bicycles), personal belongings(e.g., bags or glasses), foods, plants, animals, human bodies, clothing,everyday articles, products such as electronic appliances,identification tags on luggage, and the like. An RFID tag can be used asa so-called ID label, ID tag, or ID card. An electronic appliance refersto a liquid crystal display device, an EL display device, a televisionset (also called simply a television, a TV receiver, or a televisionreceiver), a mobile phone, or the like. Hereinafter, applications of thepresent invention and examples of products which include an applicationof the present invention are described with reference to FIGS. 23A to23E.

FIG. 23A shows an example of completed RFID tags relating to the presentinvention. A plurality of ID labels 3003 each including an RFID tag 3002are formed on a label board 3001 (separate paper). The ID labels 3003are stored in a box 3004. On the ID label 3003, there is informationabout a product or service (a product name, a brand, a trademark, atrademark owner, a seller, a manufacturer, or the like). Meanwhile, anID number that is unique to the product (or the type of product) isassigned to the included RFID tag 3002, so that illegal behavior, suchas forgery, infringement of intellectual property rights like patentrights and trademark rights, or unfair competition can easily bedetected. In addition, a large amount of information that cannot beclearly shown on a container or the label of the product, for example,production area, selling area, quality, raw materials, efficacy, use,quantity, shape, price, production method, method of use, time ofproduction, time of use, expiration date, instructions for the product,information about the intellectual property of the product, or the like,can be inputted to the RFID tag 3002 so that a client or a consumer canaccess the information using a simple reader. In addition, the RFID taghas a structure such that the producer of a product can easily rewrite,erase, or the like the information, but a client or a consumer cannot.Note that the RFID tag may have a display portion to display theinformation.

FIG. 23B shows a label-shaped RFID tag 3011 which includes an RFID tag3012. When a product is provided with the RFID tag 3011, productmanagement can be simplified. For example, in the case where the productis stolen, the product can be traced, so the culprit can be identifiedquickly. Thus, by providing products with the RFID tags, products thatare superior in so-called traceability can be distributed.

FIG. 23C shows an example of a completed ID card 3021 including an RFIDtag 3022. The ID card 3021 may be any kind of card: a cash card, acredit card, a prepaid card, an electronic ticket, electronic money, atelephone card, a membership card, or the like. Further, the ID card3021 may have a display portion on its surface to display various kindsof information.

FIG. 23D shows a completed bearer bond 3031. An RFID tag 3032 isembedded in the bearer bond 3031 and is protected by a resin which isformed in the periphery of the RFID tag. Here, the resin is filled witha filler. The bearer bond 3031 can be formed in the same manner as anRFID tag of the present invention. Note that the aforementioned bearerbond may be a stamp, a ticket, an admission ticket, a merchandisecoupon, a book coupon, a stationery coupon, a beer coupon, a ricecoupon, various types of gift coupon, various types of service coupon,or the like. Needless to say, the bearer bond is not limited thereto.When the RFID tag 3032 of the present invention is provided in bills,coins, securities, bearer bonds, documents, or the like, anauthentication function can be provided, and by using the authenticationfunction, forgery can be prevented.

FIG. 23E shows a book 3043 to which an ID label 3041 which includes anRFID tag 3042 is attached. The RFID tag 3042 of the present invention isfirmly attached in or on goods by being attached to a surface orembedded, for example. As shown in FIG. 23E, the RFID tag 3042 can beembedded in the paper of a book, or embedded in an organic resin of apackage. Because the RFID tag 3042 of the present invention can besmall, thin, and lightweight, it can be firmly attached to or in goodswithout spoiling their design.

Although not illustrated here, the efficiency of a system such as aninspection system can be improved by providing the RFID tags of thepresent invention in, for example, packaging containers, storage media,personal belongings, foods, clothing, everyday articles, electronicappliances, or the like. Further, a vehicle is provided with the RFIDtag, counterfeit and theft can be prevented. Furthermore, living thingssuch as animals can be easily identified by implanting the individualliving things with RFID tags. For example, year of birth, sex, breed,and the like can be easily recognized by implanting wireless tags inliving things such as domestic animals.

FIGS. 24A and 24B show a book 2701 and a plastic bottle 2702 to which IDlabels 2502 which include an RFID tag 2501 of the present invention areattached. Because the RFID tag 2501 that is used in the presentinvention is very thin, when the ID label 2502 is mounted on goods suchas the book, function and design of the goods are not spoiled. Further,in the case of a non-contact type thin film integrated circuit device,an antenna and a chip can be fondled over the same substrate and thenon-contact type thin film integrated circuit device can be directlytransferred to a product which has a curved surface easily.

FIG. 24C shows the ID label 2502 which includes the RFID tag 2501directly attached to fresh food, which is a piece of fruit 2705.Further, FIG. 24D shows examples of fresh food, vegetables 2704, wrappedin a wrapping film. Note that in the case of attaching a RFID tag 2501to a product, it is possible that the RFID tag 2501 might be taken off;however, in the case of wrapping the product with a wrapping film 2703,it is difficult to take off the wrapping film 2703. Therefore, to someextent, there is an advantage in preventing crimes. Note that asemiconductor device of the present invention can be applied to allkinds of products besides the above-mentioned ones.

Note that a structure of an RFID tag in this embodiment mode can beimplemented by being combined with a structure of a semiconductor devicein another embodiment mode described in this specification.

This application is based on Japanese Patent Application serial no.2006-320469 filed in Japan Patent Office on Nov. 28, 2006, the entirecontents of which are hereby incorporated by reference.

1. A method for managing an electric power in a battery of asemiconductor device, the method comprising: charging the battery of thesemiconductor device by receiving an electromagnetic wave; communicatingwith a first device comprising a battery; and sending an electromagneticwave from the semiconductor device to the first device to feed anelectric power to the battery of the first device.
 2. The methodaccording to claim 1, wherein the battery of the semiconductor device isany one of a lithium battery, a nickel metal hydride battery and adouble-layer electrolytic capacitor.
 3. A method for managing anelectric power in a battery of a semiconductor device, the methodcomprising: communicating with a first device comprising a battery;charging the battery of the semiconductor device by receiving anelectromagnetic wave from the first device; and sending anelectromagnetic wave from the semiconductor device to the first deviceto feed an electric power to the battery of the first device.
 4. Themethod according to claim 3, wherein the battery of the semiconductordevice is any one of a lithium battery, a nickel metal hydride batteryand a double-layer electrolytic capacitor.
 5. A method for managing anelectric power in a battery of a semiconductor device, the methodcomprising: communicating with a first device comprising a battery;charging the battery of the semiconductor device by receiving anelectromagnetic wave from the first device; communicating with a seconddevice comprising a battery; and sending an electromagnetic wave fromthe semiconductor device to the second device to feed an electric powerto the battery of the second device.
 6. The method according to claim 5,wherein the battery of the semiconductor device is any one of a lithiumbattery, a nickel metal hydride battery and a double-layer electrolyticcapacitor.
 7. A method for managing an electric power in a battery of asemiconductor device, the method comprising: communicating with a firstdevice comprising a battery to detect a voltage of the battery of thefirst device; comparing a voltage of the battery of the semiconductordevice with the voltage of the battery of the first device; and decidingwhether to charge the battery of the semiconductor device by receivingan electromagnetic wave from the first device or to send anelectromagnetic wave from the semiconductor device to the first deviceto feed an electric power to the battery of the first device, inaccordance with a result of the comparing.
 8. The method according toclaim 7, wherein the battery of the semiconductor device is any one of alithium battery, a nickel metal hydride battery and a double-layerelectrolytic capacitor.
 9. A method for managing an electric power in abattery of a semiconductor device, the method comprising: communicatingwith a first device comprising a battery to detect a voltage of thebattery of the first device; comparing a voltage of the battery of thesemiconductor device with a predetermined voltage; and comparing avoltage of the battery of the first device with the predeterminedvoltage, wherein the battery of the semiconductor device is charged byreceiving an electromagnetic wave from the first device if the voltageof the battery of the semiconductor device is lower than thepredetermined voltage and the voltage of the battery of the first deviceis higher than the predetermined voltage, and wherein the semiconductordevice sends an electromagnetic wave to the first device to feed anelectric power to the battery of the first device if the voltage of thebattery of the semiconductor device is higher than the predeterminedvoltage and the voltage of the battery of the first device is lower thanthe predetermined voltage.
 10. The method according to claim 9, whereinthe battery of the semiconductor device is any one of a lithium battery,a nickel metal hydride battery and a double-layer electrolyticcapacitor.
 11. A method for managing an electric power in a battery ofan RFID tag, the method comprising: charging the battery of the RFID tagby receiving an electromagnetic wave; communicating with a first otherRFID tag comprising a battery; and sending an electromagnetic wave fromthe RFID tag to the first other RFID tag to feed an electric power tothe battery of the first other RFID tag.
 12. The method according toclaim 11, wherein the battery of the RFID tag is any one of a lithiumbattery, a nickel metal hydride battery and a double-layer electrolyticcapacitor.
 13. A method for managing an electric power in a battery ofan RFID tag, the method comprising: communicating with a first otherRFID tag comprising a battery; charging the battery of the RFID tag byreceiving an electromagnetic wave from the first other RFID tag; andsending an electromagnetic wave from the RFID tag to the first otherRFID tag to feed an electric power to the battery of the first otherRFID tag.
 14. The method according to claim 13, wherein the battery ofthe RFID tag is any one of a lithium battery, a nickel metal hydridebattery and a double-layer electrolytic capacitor.
 15. A method formanaging an electric power in a battery of an RFID tag, the methodcomprising: communicating with a first other RFID tag comprising abattery; charging the battery of the RFID tag by receiving anelectromagnetic wave from the first other RFID tag; communicating with asecond other RFID tag comprising a battery; and sending anelectromagnetic wave from the RFID tag to the second other RFID tag tofeed an electric power to the battery of the second other RFID tag. 16.The method according to claim 15, wherein the battery of the RFID tag isany one of a lithium battery, a nickel metal hydride battery and adouble-layer electrolytic capacitor.
 17. A method for managing anelectric power in a battery of an RFID tag, the method comprising:communicating with a first other RFID tag comprising a battery to detecta voltage of the battery of the first other RFID tag; comparing avoltage of the battery of the RFID tag with the voltage of the batteryof the first other RFID tag; and deciding whether to charge the batteryof the RFID tag by receiving an electromagnetic wave from the firstother RFID tag or to send an electromagnetic wave from the RFID tag tothe first other RFID tag to feed an electric power to the battery of thefirst other RFID tag, in accordance with a result of the comparing. 18.The method according to claim 17, wherein the battery of the RFID tag isany one of a lithium battery, a nickel metal hydride battery and adouble-layer electrolytic capacitor.
 19. A method for managing anelectric power in a battery of an RFID tag, the method comprising:communicating with a first other RFID tag comprising a battery to detecta voltage of the battery of the first other RFID tag; comparing avoltage of the battery of the RFID tag with a predetermined voltage; andcomparing a voltage of the battery of the first other RFID tag with thepredetermined voltage, wherein the battery of the RFID tag is charged byreceiving an electromagnetic wave from the first other RFID tag if thevoltage of the battery of the RFID tag is lower than the predeterminedvoltage and the voltage of the battery of the first other RFID tag ishigher than the predetermined voltage, and wherein the RFID tag sends anelectromagnetic wave to the first other RFID tag to feed an electricpower to the battery of the first other RFID tag if the voltage of thebattery of the RFID tag is higher than the predetermined voltage and thevoltage of the battery of the first other RFID tag is lower than thepredetermined voltage.
 20. The method according to claim 19, wherein thebattery of the RFID tag is any one of a lithium battery, a nickel metalhydride battery and a double-layer electrolytic capacitor.